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  • How to use function to connect to database and how to work with queries?

    - by Abhilash Shukla
    I am using functions to work with database.. Now the way i have defined the functions are as follows:- /** * Database definations */ define ('db_type', 'MYSQL'); define ('db_host', 'localhost'); define ('db_port', '3306'); define ('db_name', 'database'); define ('db_user', 'root'); define ('db_pass', 'password'); define ('db_table_prefix', ''); /** * Database Connect */ function db_connect($host = db_host, $port = db_port, $username = db_user, $password = db_pass, $database = db_name) { if(!$db = @mysql_connect($host.':'.$port, $username, $password)) { return FALSE; } if((strlen($database) > 0) AND (!@mysql_select_db($database, $db))) { return FALSE; } // set the correct charset encoding mysql_query('SET NAMES \'utf8\''); mysql_query('SET CHARACTER_SET \'utf8\''); return $db; } /** * Database Close */ function db_close($identifier) { return mysql_close($identifier); } /** * Database Query */ function db_query($query, $identifier) { return mysql_query($query, $identifier); } Now i want to know whether it is a good way to do this or not..... Also, while database connect i am using $host = db_host Is it ok? Secondly how i can use these functions, these all code is in my FUNCTIONS.php The Database Definitions and also the Database Connect... will it do the needful for me... Using these functions how will i be able to connect to database and using the query function... how will i able to execute a query? VERY IMPORTANT: How can i make mysql to mysqli, is it can be done by just adding an 'i' to mysql....Like:- @mysql_connect @mysqli_connect

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  • Problem with circular definition in Scheme

    - by user8472
    I am currently working through SICP using Guile as my primary language for the exercises. I have found a strange behavior while implementing the exercises in chapter 3.5. I have reproduced this behavior using Guile 1.4, Guile 1.8.6 and Guile 1.8.7 on a variety of platforms and am certain it is not specific to my setup. This code works fine (and computes e): (define y (integral (delay dy) 1 0.001)) (define dy (stream-map (lambda (x) x) y)) (stream-ref y 1000) The following code should give an identical result: (define (solve f y0 dt) (define y (integral (delay dy) y0 dt)) (define dy (stream-map f y)) y) (solve (lambda (x) x) 1 0.001) But it yields the error message: standard input:7:14: While evaluating arguments to stream-map in expression (stream-map f y): standard input:7:14: Unbound variable: y ABORT: (unbound-variable) So when embedded in a procedure definition, the (define y ...) does not work, whereas outside the procedure in the global environment at the REPL it works fine. What am I doing wrong here? I can post the auxiliary code (i.e., the definitions of integral, stream-map etc.) if necessary, too. With the exception of the system-dependent code for cons-stream, they are all in the book. My own implementation of cons-stream for Guile is as follows: (define-macro (cons-stream a b) `(cons ,a (delay ,b)))

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  • error C2146: syntax error : missing ';' before identifier 'g_App'

    - by numerical25
    I wish c++, was a little more specific on the messages they give. The following error is being thrown in the document below main.h #ifndef main_h #define main_h //includes #include <windows.h> #include <commctrl.h> #include <d3d9.h> #include <fstream> #include "capplication.h" //constants #define TITLE "D3D Tut 01: Create Window" #define WINDOW_X 350 #define WINDOW_Y 320 //Button ID's #define ID_START 1 #define ID_CANCEL 2 //globals extern CApplication g_App; //function prototypes LRESULT CALLBACK WindowProcedure(HWND,UINT,WPARAM,LPARAM); #endif The only header file that could possible throw this error is the capplication.h. given below capplication.h #ifndef capplication_h #define capplication_h #include"main.h" class CApplication { public: CApplication(void); ~CApplication(void); void InitWindow(void); void SaveSettings(void); void LoadSettings(void); void KillWindow(void); inline bool GetWindowStatus(void) { return m_bRunningWindow; } inline HWND GetWindowHandle(void) { return m_hWindow; } inline void SetWindowStatus(bool bRunningWindow) { m_bRunningWindow = bRunningWindow; } private: bool m_bRunningWindow; HWND m_hWindow, m_hBtnStart, m_hBtnCancel, m_hLblResolution, m_hCbResolution, m_hLblBackBuffer, m_hCbBackBuffer, m_hLblDepthStencil, m_hCbDepthStencil, m_hLblVertexProcessing, m_hCbVertexProcessing, m_hLblMultiSampling, m_hCbMultiSampling, m_hLblAnisotropy, m_hCbAnisotropy; DWORD m_dwWidth, m_dwHeight, m_dwVertexProcessing, m_dwAnisotropy; D3DFORMAT m_ColorFormat, m_DepthStencilFormat; D3DMULTISAMPLE_TYPE m_MultiSampling; }; #endif Besides that, the only suspicious thing I see is fstream given in the first code. I did have it as fstream.h But VC++ was not recognizing it so I was told to remove the h and I did. now I am down to this error. and I have no clue what it could be. Possibly something obvious

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  • Designing an API with compile-time option to remove first parameter to most functions and use a glob

    - by tomlogic
    I'm trying to design a portable API in ANSI C89/ISO C90 to access a wireless networking device on a serial interface. The library will have multiple network layers, and various versions need to run on embedded devices as small as an 8-bit micro with 32K of code and 2K of data, on up to embedded devices with a megabyte or more of code and data. In most cases, the target processor will have a single network interface and I'll want to use a single global structure with all state information for that device. I don't want to pass a pointer to that structure through the network layers. In a few cases (e.g., device with more resources that needs to live on two networks) I will interface to multiple devices, each with their own global state, and will need to pass a pointer to that state (or an index to a state array) through the layers. I came up with two possible solutions, but neither one is particularly pretty. Keep in mind that the full driver will potentially be 20,000 lines or more, cover multiple files, and contain hundreds of functions. The first solution requires a macro that discards the first parameter for every function that needs to access the global state: // network.h typedef struct dev_t { int var; long othervar; char name[20]; } dev_t; #ifdef IF_MULTI #define foo_function( x, a, b, c) _foo_function( x, a, b, c) #define bar_function( x) _bar_function( x) #else extern dev_t DEV; #define IFACE (&DEV) #define foo_function( x, a, b, c) _foo_function( a, b, c) #define bar_function( x) _bar_function( ) #endif int bar_function( dev_t *IFACE); int foo_function( dev_t *IFACE, int a, long b, char *c); // network.c #ifndef IF_MULTI dev_t DEV; #endif int bar_function( dev_t *IFACE) { memset( IFACE, 0, sizeof *IFACE); return 0; } int foo_function( dev_t *IFACE, int a, long b, char *c) { bar_function( IFACE); IFACE->var = a; IFACE->othervar = b; strcpy( IFACE->name, c); return 0; } The second solution defines macros to use in the function declarations: // network.h typedef struct dev_t { int var; long othervar; char name[20]; } dev_t; #ifdef IF_MULTI #define DEV_PARAM_ONLY dev_t *IFACE #define DEV_PARAM DEV_PARAM_ONLY, #else extern dev_t DEV; #define IFACE (&DEV) #define DEV_PARAM_ONLY void #define DEV_PARAM #endif int bar_function( DEV_PARAM_ONLY); // I don't like the missing comma between DEV_PARAM and arg2... int foo_function( DEV_PARAM int a, long b, char *c); // network.c #ifndef IF_MULTI dev_t DEV; #endif int bar_function( DEV_PARAM_ONLY) { memset( IFACE, 0, sizeof *IFACE); return 0; } int foo_function( DEV_PARAM int a, long b, char *c) { bar_function( IFACE); IFACE->var = a; IFACE->othervar = b; strcpy( IFACE->name, c); return 0; } The C code to access either method remains the same: // multi.c - example of multiple interfaces #define IF_MULTI #include "network.h" dev_t if0, if1; int main() { foo_function( &if0, -1, 3.1415926, "public"); foo_function( &if1, 42, 3.1415926, "private"); return 0; } // single.c - example of a single interface #include "network.h" int main() { foo_function( 11, 1.0, "network"); return 0; } Is there a cleaner method that I haven't figured out? I lean toward the second since it should be easier to maintain, and it's clearer that there's some macro magic in the parameters to the function. Also, the first method requires prefixing the function names with "_" when I want to use them as function pointers. I really do want to remove the parameter in the "single interface" case to eliminate unnecessary code to push the parameter onto the stack, and to allow the function to access the first "real" parameter in a register instead of loading it from the stack. And, if at all possible, I don't want to have to maintain two separate codebases. Thoughts? Ideas? Examples of something similar in existing code? (Note that using C++ isn't an option, since some of the planned targets don't have a C++ compiler available.)

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  • How do I make a module in PLT Scheme?

    - by kunjaan
    I tried doing this: #lang scheme (module duck scheme/base (provide num-eggs quack) (define num-eggs 2) (define (quack n) (unless (zero? n) (printf "quack\n") (quack (sub1 n))))) But I get this error: module: illegal use (not at top-level) in: (module duck scheme/base (provide num-eggs quack) (define num-eggs 2) (define (quack n) (unless (zero? n) (printf "quack\n") (quack (sub1 n))))) what is the correct way?

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  • What's the C strategy to "imitate" a C++ template ?

    - by Andrei Ciobanu
    After reading some examples on stackoverflow, and following some of the answers for my previous questions (1), I've eventually come with a "strategy" for this. I've come to this: 1) Have a declare section in the .h file. Here I will define the data-structure, and the accesing interface. Eg.: /** * LIST DECLARATION. (DOUBLE LINKED LIST) */ #define NM_TEMPLATE_DECLARE_LIST(type) \ typedef struct nm_list_elem_##type##_s { \ type data; \ struct nm_list_elem_##type##_s *next; \ struct nm_list_elem_##type##_s *prev; \ } nm_list_elem_##type ; \ typedef struct nm_list_##type##_s { \ unsigned int size; \ nm_list_elem_##type *head; \ nm_list_elem_##type *tail; \ int (*cmp)(const type e1, const type e2); \ } nm_list_##type ; \ \ nm_list_##type *nm_list_new_##type##_(int (*cmp)(const type e1, \ const type e2)); \ \ (...other functions ...) 2) Wrap the functions in the interface inside MACROS: /** * LIST INTERFACE */ #define nm_list(type) \ nm_list_##type #define nm_list_elem(type) \ nm_list_elem_##type #define nm_list_new(type,cmp) \ nm_list_new_##type##_(cmp) #define nm_list_delete(type, list, dst) \ nm_list_delete_##type##_(list, dst) #define nm_list_ins_next(type,list, elem, data) \ nm_list_ins_next_##type##_(list, elem, data) (...others...) 3) Implement the functions: /** * LIST FUNCTION DEFINITIONS */ #define NM_TEMPLATE_DEFINE_LIST(type) \ nm_list_##type *nm_list_new_##type##_(int (*cmp)(const type e1, \ const type e2)) \ {\ nm_list_##type *list = NULL; \ list = nm_alloc(sizeof(*list)); \ list->size = 0; \ list->head = NULL; \ list->tail = NULL; \ list->cmp = cmp; \ }\ void nm_list_delete_##type##_(nm_list_##type *list, \ void (*destructor)(nm_list_elem_##type elem)) \ { \ type data; \ while(nm_list_size(list)){ \ data = nm_list_rem_##type(list, tail); \ if(destructor){ \ destructor(data); \ } \ } \ nm_free(list); \ } \ (...others...) In order to use those constructs, I have to create two files (let's call them templates.c and templates.h) . In templates.h I will have to NM_TEMPLATE_DECLARE_LIST(int), NM_TEMPLATE_DECLARE_LIST(double) , while in templates.c I will need to NM_TEMPLATE_DEFINE_LIST(int) , NM_TEMPLATE_DEFINE_LIST(double) , in order to have the code behind a list of ints, doubles and so on, generated. By following this strategy I will have to keep all my "template" declarations in two files, and in the same time, I will need to include templates.h whenever I need the data structures. It's a very "centralized" solution. Do you know other strategy in order to "imitate" (at some point) templates in C++ ? Do you know a way to improve this strategy, in order to keep things in more decentralized manner, so that I won't need the two files: templates.c and templates.h ?

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  • WordPress 3.5 Multisite and nginx siteurl issues

    - by Florin Gogianu
    I'm setting up multisite on localhost in subdirectories. The problem is that when I'm trying to access the dashboard of a site I just created ( localhost/wptest/site/wp-admin ) I get "This webpage has a redirect loop" and when I try to access the actual website ( localhost/wptest/site ) the page loads but without assets, such as css. When I access the network dashboard, or the primary site dashboard on localhost/wptest everything is just fine. Also when I edit the permalink of the second site in the network dashboard, to be like this: localhost/site it also runs fine. How to make it work with the default permalink structure localhost/wptest/site? The wordpress files are in /usr/share/html/wptest The wp-config.php is as follows: define('WP_ALLOW_MULTISITE', true); define('MULTISITE', true); define('SUBDOMAIN_INSTALL', false); define('DOMAIN_CURRENT_SITE', 'localhost'); define('PATH_CURRENT_SITE', '/wptest/'); define('SITE_ID_CURRENT_SITE', 1); define('BLOG_ID_CURRENT_SITE', 1); And the server block / virtual host is like this: server { ##DM - uncomment following line for domain mapping listen 80 default_server; #server_name example.com *.example.com ; ##DM - uncomment following line for domain mapping #server_name_in_redirect off; access_log /var/log/nginx/example.com.access.log; error_log /var/log/nginx/example.com.error.log; root /usr/share/nginx/html/wptest; index index.html index.htm index.php; if (!-e $request_filename) { rewrite /wp-admin$ $scheme://$host$uri/ permanent; rewrite ^(/[^/]+)?(/wp-.*) $2 last; rewrite ^(/[^/]+)?(/.*\.php) $2 last; } location / { try_files $uri $uri/ /index.php?$args ; } location ~ \.php$ { try_files $uri /index.php; include fastcgi_params; fastcgi_pass unix:/var/run/php5-fpm.sock; } location ~* ^.+\.(ogg|ogv|svg|svgz|eot|otf|woff|mp4|ttf|rss|atom|jpg|jpeg|gif|png|ico|zip|tgz|gz|rar|bz2|doc|xls|exe|ppt|tar|mid|midi|wav|bmp|rtf)$ { access_log off; log_not_found off; expires max; } location = /robots.txt { access_log off; log_not_found off; } location ~ /\. { deny all; access_log off; log_not_found off; } } And finally here's an error log: 2013/06/29 08:05:37 [error] 4056#0: *52 rewrite or internal redirection cycle while internally redirecting to "/index.php", client: 127.0.0.1, server: example.com, request: "GET /nginx HTTP/1.1", host: "localhost"

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  • Is there a C pre-processor which eliminates #ifdef blocks based on values defined/undefined?

    - by Jonathan Leffler
    Original Question What I'd like is not a standard C pre-processor, but a variation on it which would accept from somewhere - probably the command line via -DNAME1 and -UNAME2 options - a specification of which macros are defined, and would then eliminate dead code. It may be easier to understand what I'm after with some examples: #ifdef NAME1 #define ALBUQUERQUE "ambidextrous" #else #define PHANTASMAGORIA "ghostly" #endif If the command were run with '-DNAME1', the output would be: #define ALBUQUERQUE "ambidextrous" If the command were run with '-UNAME1', the output would be: #define PHANTASMAGORIA "ghostly" If the command were run with neither option, the output would be the same as the input. This is a simple case - I'd be hoping that the code could handle more complex cases too. To illustrate with a real-world but still simple example: #ifdef USE_VOID #ifdef PLATFORM1 #define VOID void #else #undef VOID typedef void VOID; #endif /* PLATFORM1 */ typedef void * VOIDPTR; #else typedef mint VOID; typedef char * VOIDPTR; #endif /* USE_VOID */ I'd like to run the command with -DUSE_VOID -UPLATFORM1 and get the output: #undef VOID typedef void VOID; typedef void * VOIDPTR; Another example: #ifndef DOUBLEPAD #if (defined NT) || (defined OLDUNIX) #define DOUBLEPAD 8 #else #define DOUBLEPAD 0 #endif /* NT */ #endif /* !DOUBLEPAD */ Ideally, I'd like to run with -UOLDUNIX and get the output: #ifndef DOUBLEPAD #if (defined NT) #define DOUBLEPAD 8 #else #define DOUBLEPAD 0 #endif /* NT */ #endif /* !DOUBLEPAD */ This may be pushing my luck! Motivation: large, ancient code base with lots of conditional code. Many of the conditions no longer apply - the OLDUNIX platform, for example, is no longer made and no longer supported, so there is no need to have references to it in the code. Other conditions are always true. For example, features are added with conditional compilation so that a single version of the code can be used for both older versions of the software where the feature is not available and newer versions where it is available (more or less). Eventually, the old versions without the feature are no longer supported - everything uses the feature - so the condition on whether the feature is present or not should be removed, and the 'when feature is absent' code should be removed too. I'd like to have a tool to do the job automatically because it will be faster and more reliable than doing it manually (which is rather critical when the code base includes 21,500 source files). (A really clever version of the tool might read #include'd files to determine whether the control macros - those specified by -D or -U on the command line - are defined in those files. I'm not sure whether that's truly helpful except as a backup diagnostic. Whatever else it does, though, the pseudo-pre-processor must not expand macros or include files verbatim. The output must be source similar to, but usually simpler than, the input code.) Status Report (one year later) After a year of use, I am very happy with 'sunifdef' recommended by the selected answer. It hasn't made a mistake yet, and I don't expect it to. The only quibble I have with it is stylistic. Given an input such as: #if (defined(A) && defined(B)) || defined(C) || (defined(D) && defined(E)) and run with '-UC' (C is never defined), the output is: #if defined(A) && defined(B) || defined(D) && defined(E) This is technically correct because '&&' binds tighter than '||', but it is an open invitation to confusion. I would much prefer it to include parentheses around the sets of '&&' conditions, as in the original: #if (defined(A) && defined(B)) || (defined(D) && defined(E)) However, given the obscurity of some of the code I have to work with, for that to be the biggest nit-pick is a strong compliment; it is valuable tool to me. The New Kid on the Block Having checked the URL for inclusion in the information above, I see that (as predicted) there is an new program called Coan that is the successor to 'sunifdef'. It is available on SourceForge and has been since January 2010. I'll be checking it out...further reports later this year, or maybe next year, or sometime, or never.

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  • Conflicting PACKAGE_NAME and other macros when using autotools.

    - by baol
    When using autotools (with a config.h file) for both a library and a software built on that library the compiler complains about a redefinition of some macros (PACKAGE_NAME, PACKAGE_TARNAME and so on). How can I prevent this? The config.h file is needed in the library to propagate it's setting to the software that use it. Right now I have a wrapper script library_config.h that includes the original config.h and provides defaults when the user is not using autotools, but even undefining the macros in that package I get the redefinition warning from gcc. #ifndef LIB_CONFIG_H #define LIB_CONFIG_H #ifdef HAVE_CONFIG_H # include "config.h" # undef PACKAGE # undef PACKAGE_BUGREPORT # undef PACKAGE_NAME # undef PACKAGE_STRING # undef PACKAGE_TARNAME # undef PACKAGE_VERSION # undef VERSION #else # if defined (WIN32) # define HAVE_UNORDERED_MAP 1 # define TR1_MIXED_NAMESPACE 1 # elif defined (__GXX_EXPERIMENTAL_CXX0X__) # define HAVE_UNORDERED_MAP 1 # else # define HAVE_TR1_UNORDERED_MAP 1 # endif #endif #endif I believe the best option would be to have a library without that macros: How can I avoid the definition of PACKAGE, PACKAGE_NAME and so on in the library when using autotools?

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  • Which OpenGL version is installed?

    - by René Nyffenegger
    I recently tried to lay my hands on OpenGL. Trying to grasp the API, I learned (or was given the advice) that I shouldn't use glBegin and glEnd anymore, since those are deprecated, but should start with OpenGL 3.1, instead. As I didn't know that the version used makes such a difference, I didn't pay much attention as to which version I actually have installed on my computer. And, as far as I can see, there is no glVersion or similar call that I could use to determine that version. I am using MinGW and I found the following lines in c:\MinGW\include\GL\gl.h: /* * Mesa 3-D graphics library * Version: 4.0 [more lines] */ [more lines] #define GL_VERSION_1_1 1 #if !defined(__WIN32__) #define GL_VERSION_1_2 1 #define GL_VERSION_1_3 1 #define GL_ARB_imaging 1 #endif [more lines] #define GL_VERSION 0x1F02 which, to me, indicates, that the installed version is as low as 1.3. Is this the case or how could I verify my suspicion? Also, where would I find a later version if I have 1.3 only?

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  • PLT Scheme URL dispatch

    - by Inaimathi
    I'm trying to hook up URL dispatch with PLT Scheme. I've taken a look at the tutorial and the server documentation. I can figure out how to route requests to the same servlets. Specific example: (define (start request) (blog-dispatch request)) (define-values (blog-dispatch blog-url) (dispatch-rules (("") list-posts) (("posts" (string-arg)) review-post) (("archive" (integer-arg) (integer-arg)) review-archive) (else list-posts))) (define (list-posts req) `(list-posts)) (define (review-post req p) `(review-post ,p)) (define (review-archive req y m) `(review-archive ,y ,m)) Assuming the above code running on a server listening 8080, localhost:8080/ goes to a page that says "list-posts". Going to localhost:8080/posts/test goes to a PLT "file not found" page (with the above code, I'd expect it to go to a page that says "review-post test"). It feels like I'm missing something small and obvious. Can anyone give me a hint?

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  • Can one .PHP file edit another?

    - by Ole Jak
    So I have a file for constants. I want to let user define them and then edit my .php filr with that global constants (not xml - real PHP file ) With such code for example <?php // Database Constants define("DB_SERVER", "localhost"); define("DB_USER", "root"); define("DB_PASS", "000000"); define("DB_NAME", "cms"); ?> How to edit this .php file from another PHP file? Is it possible? Btw in future I want to implement not only constants redefining but some smart code that will be able to modify itself.

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  • Objective-C Custom extend

    - by ryanjm.mp
    I have a couple classes that have nearly identical code. Only a string or two is different between them. What I would like to do is to make them from another class that defines those functions and then uses constants or something else to define those strings that are different. I'm not sure if "___" is inheritance or extending or what. That is what I need help with. For example: objectA.m: -(void)helloWorld { NSLog("Hello %@",child.name); } objectBob.m: #define name @"Bob" objectJoe.m #define name @"Joe" (I'm not sure if it's legal to define strings, but this gets the point across) It would be ideal if objectBob.m and objectJoe.m didn't have to even define the methods, just their relationship to objectA.m. Is there any way to do something like this? If all else fails I'll just make objectA.m: -(void)helloWorld:(NSString *name) { NSLog("Hello %@",name); } And have the other files call that function (and just #import objectA.m).

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  • how to solve nested list programs [closed]

    - by riya
    write a function to get most popular car that accepts a car detail as input and returns the most popular car name along with its average rating .Each element of car details list is a sublist that provides the below information about a car (a)name of a car(b)car price (c) list of ratings obtained by car from various agencies.Incase two cars have the same average rating then the car with the lesser price qualifies as most popular car? here's my solution-: (define-struct cardetails ("name" price list of '(ratings)) (define car1 (make-cardetails "toyota" 123 '( 1 2 3))) (define car2 (make-cardetails "santro" 321 '( 2 2 3))) (define car3 (make-cardetails "toyota" 100 '( 1 2 3))) (define cardetailslist(list(car1) (car2)(car 3))) (let loop ((count 0)) (let (len (length cardetailslist)) (if(< count len) (string-ref (string-ref n)0) now please tell me how to find maximum average and display car name.it's not a homework question tomorrow is my test and we have not been taught this concept in class although it is very important from test point of view

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  • Including C header file with lots of global variables

    - by Costi
    I have an include file with 100+ global variables. It's being used in a library, but some programs that I'm linking the lib to also need to access the globals. The way it was built: // In one library .c file #define Extern // In the programs that use the globals #define Extern extern // In the .h file Extern int a,b,c; I had a hard time understanding why the original programmer did that so I removed that define Extern stuff. Now I think I understand the thing about TU with the help of stackoverflow: 1, 2, 3. Now I understand that I should define the global variables in one .c file in the library and use extern in the .h file. The problem is that I don't want to duplicate code. Should I go back to that #define Extern voodoo?

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  • Speed up executable program Linux. Bit Toggling

    - by AK_47
    I have a ZyBo circuit board which has a ArmV7 processor. I wrote a C program to output a clock and a corresponding data sequence on a PMOD. The PMOD has a switching speed of up to 50MHz. However, my program's created clock only has a max frequency of 115 Hz. I need this program to output as fast as possible because the PMOD I'm using is capable of 50MHz. I compiled my program with the following code line: gcc -ofast (c_program) Here is some sample code: #include <stdio.h> #include <stdlib.h> #define ARRAYSIZE 511 //________________________________________ //macro for the SIGNAL PMOD //________________________________________ //DATA //ZYBO Use Pin JE1 #define INIT_SIGNAL system("echo 54 > /sys/class/gpio/export"); system("echo out > /sys/class/gpio/gpio54/direction"); #define SIGNAL_ON system("echo 1 > /sys/class/gpio/gpio54/value"); #define SIGNAL_OFF system("echo 0 > /sys/class/gpio/gpio54/value"); //________________________________________ //macro for the "CLOCK" PMOD //________________________________________ //CLOCK //ZYBO Use Pin JE4 #define INIT_MYCLOCK system("echo 57 > /sys/class/gpio/export"); system("echo out > /sys/class/gpio/gpio57/direction"); #define MYCLOCK_ON system("echo 1 > /sys/class/gpio/gpio57/value"); #define MYCLOCK_OFF system("echo 0 > /sys/class/gpio/gpio57/value"); int main(void){ int myarray[ARRAYSIZE] = {//hard coded array for signal data 1,0,0,1,0,1,0,0,1,0,1,0,0,1,0,1,0,0,1,0,1,0,0,1,0,0,1,0,1,0,0,1,1,0,0,1,1,0,1,0,0,0,0,0,1,0,0,1,1,1,0,0,1,1,1,0,1,1,1,1,0,0,1,0,0,0,1,0,1,0,0,1,1,1,0,0,1,0,1,0,1,0,0,1,0,1,1,0,1,0,1,1,0,0,1,1,1,1,0,0,1,0,1,0,0,1,1,1,1,1,1,0,0,1,0,0,1,1,0,1,0,0,0,0,1,0,0,0,1,1,0,0,1,0,1,1,1,0,0,0,1,0,0,0,1,0,1,0,0,0,1,0,0,1,0,1,1,1,1,0,1,1,0,1,0,0,1,0,0,0,1,0,1,0,0,1,0,0,0,1,0,0,0,1,0,1,0,1,0,1,0,1,1,0,0,0,0,0,0,0,0,1,0,1,1,0,1,1,1,1,1,0,0,1,1,1,0,0,1,1,0,1,1,0,1,1,1,0,0,1,1,1,1,1,0,0,1,0,1,0,1,0,1,1,0,1,0,0,0,1,1,1,0,1,0,1,0,1,0,1,0,1,0,1,0,0,1,0,0,0,0,1,1,1,0,1,1,1,1,0,1,1,0,1,0,1,0,1,0,0,1,0,1,1,1,0,1,1,1,0,0,1,1,1,0,1,0,0,1,0,1,1,1,1,1,0,1,1,1,1,1,1,1,0,1,1,0,0,1,0,1,1,0,1,0,1,1,1,0,0,0,0,0,1,0,0,0,1,0,1,1,1,1,1,1,1,0,0,0,0,0,1,1,0,1,1,1,1,1,1,1,1,0,1,1,0,1,0,0,0,1,1,1,1,1,1,1,1,1,1,0,1,1,1,1,0,1,1,1,0,1,0,1,1,1,0,0,0,1,0,1,0,1,0,0,1,1,0,0,1,1,0,1,0,0,1,0,0,1,0,1,1,1,1,1,1,0,1,1,0,1,0,1,1,1,1,1,1,0,0,1,1,0,1,1,0,0,1,1,0,1,1,0,1,0,1,0,1,0,1,0,0,1,1,1,0,1,1,0,0,0,0,1,1,0,1,1,0,1,1,1,1,1,1,1,0,1,0,1,1,0,0,0,0,0,0,0,0,0,0,0 }; INIT_SIGNAL INIT_MYCLOCK; //infinite loop int i; do{ i = 0; do{ /* 1020 is chosen because it is twice the size needed allowing for the changes in the clock. (511= 0-510, 510*2= 1020 ==> 0-1020 needed, so 1021 it is) */ if((i%2)==0) { MYCLOCK_ON; if(myarray[i/2] == 1){ SIGNAL_ON; }else{ SIGNAL_OFF; } } else if((i%2)==1) { MYCLOCK_OFF; //dont need to change the signal since it will just stay at whatever it was. } ++i; } while(i < 1021); } while(1); return 0; } I'm using the 'system' call to tell the system to output 1 volt or 0 volts onto a pin on the board (to represent the data signal and clock signal. One pin for the data and another for the clock). That was the only way I knew to tell the system to output a voltage. What can I do to make my executable program output to be at least in the magnitude of MegaHertz?

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  • Rails 3 namespacing requires model to be defined twice?

    - by RSG
    I'm pulling my hair out trying to understand namespacing in Rails 3. I've tried following a few different tutorials, and the only way I can get my models to work is if I define my model in both the base directory and my namespace directory. If I only define the model in the namespace directory it expects it to define both Model and Namespace::Model, as below: LoadError (Expected .../app/models/plugins/chat.rb to define Chat): or LoadError (Expected .../app/models/plugins/chat.rb to define Plugins::Chat): I'm sure I'm missing something obvious, but I could really use a pointer in the right direction. Here are the relevant excerpts. /models/plugins/chat.rb class Plugins::Chat include ActiveModel::Validations include ActiveModel::Conversion extend ActiveModel::Naming ... end /controllers/plugins/chats_controller.rb class Plugins::ChatsController < Plugins::ApplicationController load_and_authorize_resource ... end /config/routes.rb namespace :plugins do resources :chats end /config/application.rb config.autoload_paths += Dir["#{config.root}/app/models/**/"]

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  • Extra line breaks inserted in MrEd text%

    - by Jesse Millikan
    In a DrScheme project, I'm using a MrEd editor-canvas% with text% and inserting a string from a literal in a Scheme file. This results in an extra blank line in the editor for each line of text I'm trying to insert. Is this a Windows vs. Unix linebreak problem? I can't find anything about text% treats line breaks in the documentation. ; Inside a class definition: (define/public (edit-pattern p j b d h) (send input-beat set-value (number->string b)) (send input-dwell set-value (number->string d)) (send hold-beats set-value (number->string h)) (send juggler-t erase) ; Why do these add extra newlines (send juggler-t insert j) (send pattern-t erase) (send pattern-t insert p)) (define juggler-ec (new editor-canvas% [parent this] [line-count 12])) (define juggler-t (new text%)) (send juggler-ec set-editor juggler-t) (define pattern-ec (new editor-canvas% [parent this] [line-count 20])) (define pattern-t (new text%)) (send pattern-ec set-editor pattern-t) ; Lots of other stuff...

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  • scrolling lags in emacs 23.2 with GTK

    - by mefiX
    Hey there, I am using emacs 23.2 with the GTK toolkit. I built emacs from source using the following configure-params: ./configure --prefix=/usr --without-makeinfo --without-sound Which builds emacs with the following configuration: Where should the build process find the source code? /home/****/incoming/emacs-23.2 What operating system and machine description files should Emacs use? `s/gnu-linux.h' and `m/intel386.h' What compiler should emacs be built with? gcc -g -O2 -Wdeclaration-after-statement -Wno-pointer-sign Should Emacs use the GNU version of malloc? yes (Using Doug Lea's new malloc from the GNU C Library.) Should Emacs use a relocating allocator for buffers? yes Should Emacs use mmap(2) for buffer allocation? no What window system should Emacs use? x11 What toolkit should Emacs use? GTK Where do we find X Windows header files? Standard dirs Where do we find X Windows libraries? Standard dirs Does Emacs use -lXaw3d? no Does Emacs use -lXpm? yes Does Emacs use -ljpeg? yes Does Emacs use -ltiff? yes Does Emacs use a gif library? yes -lgif Does Emacs use -lpng? yes Does Emacs use -lrsvg-2? no Does Emacs use -lgpm? yes Does Emacs use -ldbus? yes Does Emacs use -lgconf? no Does Emacs use -lfreetype? yes Does Emacs use -lm17n-flt? no Does Emacs use -lotf? yes Does Emacs use -lxft? yes Does Emacs use toolkit scroll bars? yes When I'm scrolling within files of a common size (about 1000 lines) holding the up/down-keys, emacs almost hangs and produces about 50% CPU-load. I use the following plugins: ido linum tabbar auto-complete-config Starting emacs with -q fixes the problem, but then I don't have any plugins. I can't figure out, which part of my .emacs is responsible for this behaviour. Here's an excerpt of my .emacs-file: (require 'ido) (ido-mode 1) (require 'linum) (global-linum-mode 1) (require 'tabbar) (tabbar-mode 1) (tabbar-local-mode 0) (tabbar-mwheel-mode 0) (setq tabbar-buffer-groups-function (lambda () (list "All"))) (global-set-key [M-left] 'tabbar-backward) (global-set-key [M-right] 'tabbar-forward) ;; hide the toolbar (gtk etc.) (tool-bar-mode -1) ;; Mouse scrolling enhancements (setq mouse-wheel-progressive-speed nil) (setq mouse-wheel-scroll-amount '(5 ((shift) . 5) ((control) . nil))) ;; Smart-HOME (defun smart-beginning-of-line () "Forces the cursor to jump to the first none whitespace char of the current line when pressing HOME" (interactive) (let ((oldpos (point))) (back-to-indentation) (and (= oldpos (point)) (beginning-of-line)))) (put 'smart-beginning-of-line 'CUA 'move) (global-set-key [home] 'smart-beginning-of-line) (custom-set-variables ;; custom-set-variables was added by Custom. ;; If you edit it by hand, you could mess it up, so be careful. ;; Your init file should contain only one such instance. ;; If there is more than one, they won't work right. '(column-number-mode t) '(cua-mode t nil (cua-base)) '(custom-buffer-indent 4) '(delete-selection-mode nil) '(display-time-24hr-format t) '(display-time-day-and-date 1) '(display-time-mode t) '(global-font-lock-mode t nil (font-lock)) '(inhibit-startup-buffer-menu t) '(inhibit-startup-screen t) '(pc-select-meta-moves-sexps t) '(pc-select-selection-keys-only t) '(pc-selection-mode t nil (pc-select)) '(scroll-bar-mode (quote right)) '(show-paren-mode t) '(standard-indent 4) '(uniquify-buffer-name-style (quote forward) nil (uniquify))) (setq-default tab-width 4) (setq-default indent-tabs-mode t) (setq c-basic-offset 4) ;; Highlighting of the current line (global-hl-line-mode 1) (set-face-background 'hl-line "#E8F2FE") (defalias 'yes-or-no-p 'y-or-n-p) (display-time) (set-language-environment "Latin-1") ;; Change cursor color according to mode (setq djcb-read-only-color "gray") ;; valid values are t, nil, box, hollow, bar, (bar . WIDTH), hbar, ;; (hbar. HEIGHT); see the docs for set-cursor-type (setq djcb-read-only-cursor-type 'hbar) (setq djcb-overwrite-color "red") (setq djcb-overwrite-cursor-type 'box) (setq djcb-normal-color "black") (setq djcb-normal-cursor-type 'bar) (defun djcb-set-cursor-according-to-mode () "change cursor color and type according to some minor modes." (cond (buffer-read-only (set-cursor-color djcb-read-only-color) (setq cursor-type djcb-read-only-cursor-type)) (overwrite-mode (set-cursor-color djcb-overwrite-color) (setq cursor-type djcb-overwrite-cursor-type)) (t (set-cursor-color djcb-normal-color) (setq cursor-type djcb-normal-cursor-type)))) (add-hook 'post-command-hook 'djcb-set-cursor-according-to-mode) (define-key global-map '[C-right] 'forward-sexp) (define-key global-map '[C-left] 'backward-sexp) (define-key global-map '[s-left] 'windmove-left) (define-key global-map '[s-right] 'windmove-right) (define-key global-map '[s-up] 'windmove-up) (define-key global-map '[s-down] 'windmove-down) (define-key global-map '[S-down-mouse-1] 'mouse-stay-and-copy) (define-key global-map '[C-M-S-down-mouse-1] 'mouse-stay-and-swap) (define-key global-map '[S-mouse-2] 'mouse-yank-and-kill) (define-key global-map '[C-S-down-mouse-1] 'mouse-stay-and-kill) (define-key global-map "\C-a" 'mark-whole-buffer) (custom-set-faces ;; custom-set-faces was added by Custom. ;; If you edit it by hand, you could mess it up, so be careful. ;; Your init file should contain only one such instance. ;; If there is more than one, they won't work right. '(default ((t (:inherit nil :stipple nil :background "#f7f9fa" :foreground "#191919" :inverse-video nil :box nil :strike-through nil :overline nil :underline nil :slant normal :weight normal :height 98 :width normal :foundry "unknown" :family "DejaVu Sans Mono")))) '(font-lock-builtin-face ((((class color) (min-colors 88) (background light)) (:foreground "#642880" :weight bold)))) '(font-lock-comment-face ((((class color) (min-colors 88) (background light)) (:foreground "#3f7f5f")))) '(font-lock-constant-face ((((class color) (min-colors 88) (background light)) (:weight bold)))) '(font-lock-doc-face ((t (:inherit font-lock-string-face :foreground "#3f7f5f")))) '(font-lock-function-name-face ((((class color) (min-colors 88) (background light)) (:foreground "Black" :weight bold)))) '(font-lock-keyword-face ((((class color) (min-colors 88) (background light)) (:foreground "#7f0055" :weight bold)))) '(font-lock-preprocessor-face ((t (:inherit font-lock-builtin-face :foreground "#7f0055" :weight bold)))) '(font-lock-string-face ((((class color) (min-colors 88) (background light)) (:foreground "#0000c0")))) '(font-lock-type-face ((((class color) (min-colors 88) (background light)) (:foreground "#7f0055" :weight bold)))) '(font-lock-variable-name-face ((((class color) (min-colors 88) (background light)) (:foreground "Black")))) '(minibuffer-prompt ((t (:foreground "medium blue")))) '(mode-line ((t (:background "#222222" :foreground "White")))) '(tabbar-button ((t (:inherit tabbar-default :foreground "dark red")))) '(tabbar-button-highlight ((t (:inherit tabbar-default :background "white" :box (:line-width 2 :color "white"))))) '(tabbar-default ((t (:background "gray90" :foreground "gray50" :box (:line-width 3 :color "gray90") :height 100)))) '(tabbar-highlight ((t (:underline t)))) '(tabbar-selected ((t (:inherit tabbar-default :foreground "blue" :weight bold)))) '(tabbar-separator ((t nil))) '(tabbar-unselected ((t (:inherit tabbar-default))))) Any suggestions? Kind regards, mefiX

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  • Where to find xmoov port to C#? (to make Http Pseudo Streaming from c# app)

    - by Ole Jak
    So I found this beautifull script for FLV video format Http Pseudo Streaming but in is in PHP ( found on http://stream.xmoov.com/ ) So does any one know opensource translations or can translate such PHP code into C#? <?php /* xmoov-php 1.0 Development version 0.9.3 beta by: Eric Lorenzo Benjamin jr. webmaster (AT) xmoov (DOT) com originally inspired by Stefan Richter at flashcomguru.com bandwidth limiting by Terry streamingflvcom (AT) dedicatedmanagers (DOT) com This work is licensed under the Creative Commons Attribution-NonCommercial-ShareAlike 3.0 License. For more information, visit http://creativecommons.org/licenses/by-nc-sa/3.0/ For the full license, visit http://creativecommons.org/licenses/by-nc-sa/3.0/legalcode or send a letter to Creative Commons, 543 Howard Street, 5th Floor, San Francisco, California, 94105, USA. */ // SCRIPT CONFIGURATION //------------------------------------------------------------------------------------------ // MEDIA PATH // // you can configure these settings to point to video files outside the public html folder. //------------------------------------------------------------------------------------------ // points to server root define('XMOOV_PATH_ROOT', ''); // points to the folder containing the video files. define('XMOOV_PATH_FILES', 'video/'); //------------------------------------------------------------------------------------------ // SCRIPT BEHAVIOR //------------------------------------------------------------------------------------------ //set to TRUE to use bandwidth limiting. define('XMOOV_CONF_LIMIT_BANDWIDTH', TRUE); //set to FALSE to prohibit caching of video files. define('XMOOV_CONF_ALLOW_FILE_CACHE', FALSE); //------------------------------------------------------------------------------------------ // BANDWIDTH SETTINGS // // these settings are only needed when using bandwidth limiting. // // bandwidth is limited my sending a limited amount of video data(XMOOV_BW_PACKET_SIZE), // in specified time intervals(XMOOV_BW_PACKET_INTERVAL). // avoid time intervals over 1.5 seconds for best results. // // you can also control bandwidth limiting via http command using your video player. // the function getBandwidthLimit($part) holds three preconfigured presets(low, mid, high), // which can be changed to meet your needs //------------------------------------------------------------------------------------------ //set how many kilobytes will be sent per time interval define('XMOOV_BW_PACKET_SIZE', 90); //set the time interval in which data packets will be sent in seconds. define('XMOOV_BW_PACKET_INTERVAL', 0.3); //set to TRUE to control bandwidth externally via http. define('XMOOV_CONF_ALLOW_DYNAMIC_BANDWIDTH', TRUE); //------------------------------------------------------------------------------------------ // DYNAMIC BANDWIDTH CONTROL //------------------------------------------------------------------------------------------ function getBandwidthLimit($part) { switch($part) { case 'interval' : switch($_GET[XMOOV_GET_BANDWIDTH]) { case 'low' : return 1; break; case 'mid' : return 0.5; break; case 'high' : return 0.3; break; default : return XMOOV_BW_PACKET_INTERVAL; break; } break; case 'size' : switch($_GET[XMOOV_GET_BANDWIDTH]) { case 'low' : return 10; break; case 'mid' : return 40; break; case 'high' : return 90; break; default : return XMOOV_BW_PACKET_SIZE; break; } break; } } //------------------------------------------------------------------------------------------ // INCOMING GET VARIABLES CONFIGURATION // // use these settings to configure how video files, seek position and bandwidth settings are accessed by your player //------------------------------------------------------------------------------------------ define('XMOOV_GET_FILE', 'file'); define('XMOOV_GET_POSITION', 'position'); define('XMOOV_GET_AUTHENTICATION', 'key'); define('XMOOV_GET_BANDWIDTH', 'bw'); // END SCRIPT CONFIGURATION - do not change anything beyond this point if you do not know what you are doing //------------------------------------------------------------------------------------------ // PROCESS FILE REQUEST //------------------------------------------------------------------------------------------ if(isset($_GET[XMOOV_GET_FILE]) && isset($_GET[XMOOV_GET_POSITION])) { // PROCESS VARIABLES # get seek position $seekPos = intval($_GET[XMOOV_GET_POSITION]); # get file name $fileName = htmlspecialchars($_GET[XMOOV_GET_FILE]); # assemble file path $file = XMOOV_PATH_ROOT . XMOOV_PATH_FILES . $fileName; # assemble packet interval $packet_interval = (XMOOV_CONF_ALLOW_DYNAMIC_BANDWIDTH && isset($_GET[XMOOV_GET_BANDWIDTH])) ? getBandwidthLimit('interval') : XMOOV_BW_PACKET_INTERVAL; # assemble packet size $packet_size = ((XMOOV_CONF_ALLOW_DYNAMIC_BANDWIDTH && isset($_GET[XMOOV_GET_BANDWIDTH])) ? getBandwidthLimit('size') : XMOOV_BW_PACKET_SIZE) * 1042; # security improved by by TRUI www.trui.net if (!file_exists($file)) { print('<b>ERROR:</b> xmoov-php could not find (' . $fileName . ') please check your settings.'); exit(); } if(file_exists($file) && strrchr($fileName, '.') == '.flv' && strlen($fileName) > 2 && !eregi(basename($_SERVER['PHP_SELF']), $fileName) && ereg('^[^./][^/]*$', $fileName)) { # stay clean @ob_end_clean(); @set_time_limit(0); # keep binary data safe set_magic_quotes_runtime(0); $fh = fopen($file, 'rb') or die ('<b>ERROR:</b> xmoov-php could not open (' . $fileName . ')'); $fileSize = filesize($file) - (($seekPos > 0) ? $seekPos + 1 : 0); // SEND HEADERS if(!XMOOV_CONF_ALLOW_FILE_CACHE) { # prohibit caching (different methods for different clients) session_cache_limiter("nocache"); header("Expires: Thu, 19 Nov 1981 08:52:00 GMT"); header("Last-Modified: " . gmdate("D, d M Y H:i:s") . " GMT"); header("Cache-Control: no-store, no-cache, must-revalidate, post-check=0, pre-check=0"); header("Pragma: no-cache"); } # content headers header("Content-Type: video/x-flv"); header("Content-Disposition: attachment; filename=\"" . $fileName . "\""); header("Content-Length: " . $fileSize); # FLV file format header if($seekPos != 0) { print('FLV'); print(pack('C', 1)); print(pack('C', 1)); print(pack('N', 9)); print(pack('N', 9)); } # seek to requested file position fseek($fh, $seekPos); # output file while(!feof($fh)) { # use bandwidth limiting - by Terry if(XMOOV_CONF_LIMIT_BANDWIDTH) { # get start time list($usec, $sec) = explode(' ', microtime()); $time_start = ((float)$usec + (float)$sec); # output packet print(fread($fh, $packet_size)); # get end time list($usec, $sec) = explode(' ', microtime()); $time_stop = ((float)$usec + (float)$sec); # wait if output is slower than $packet_interval $time_difference = $time_stop - $time_start; # clean up @flush(); @ob_flush(); if($time_difference < (float)$packet_interval) { usleep((float)$packet_interval * 1000000 - (float)$time_difference * 1000000); } } else { # output file without bandwidth limiting print(fread($fh, filesize($file))); } } } } ?>

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  • Why does Graphviz fail on gvLayout?

    - by David Brown
    Once again, here I am writing C without really knowing what I'm doing... I've slapped together a simple function that I can call from a C# program that takes a DOT string, an output format, and a file name and renders a graph using Graphviz. #include "types.h" #include "graph.h" #include "gvc.h" #define FUNC_EXPORT __declspec(dllexport) // Return codes #define GVUTIL_SUCCESS 0 #define GVUTIL_ERROR_GVC 1 #define GVUTIL_ERROR_DOT 2 #define GVUTIL_ERROR_LAYOUT 3 #define GVUTIL_ERROR_RENDER 4 FUNC_EXPORT int RenderDot(char * dotData, const char * format, const char * fileName) { Agraph_t * g; // The graph GVC_t * gvc; // The Graphviz context int result; // Result of layout and render operations // Create a new graphviz context gvc = gvContext(); if (!gvc) return GVUTIL_ERROR_GVC; // Read the DOT data into the graph g = agmemread(dotData); if (!g) return GVUTIL_ERROR_DOT; // Layout the graph result = gvLayout(gvc, g, "dot"); if (result) return GVUTIL_ERROR_LAYOUT; // Render the graph result = gvRenderFilename(gvc, g, format, fileName); if (result) return GVUTIL_ERROR_RENDER; // Free the layout gvFreeLayout(gvc, g); // Close the graph agclose(g); // Free the graphviz context gvFreeContext(gvc); return GVUTIL_SUCCESS; } It compiles fine, but when I call it, I get GVUTIL_ERROR_LAYOUT. At first, I thought it might have been how I was declaring my P/Invoke signature, so I tested it from a C program instead, but it still failed in the same way. RenderDot("digraph graphname { a -> b -> c; }", "png", "C:\testgraph.png"); Did I miss something? EDIT If there's a chance it has to do with how I'm compiling the code, here's the command I'm using: cl gvutil.c /I "C:\Program Files (x86)\Graphviz2.26\include\graphviz" /LD /link /LIBPATH:"C:\Program Files (x86)\Graphviz2.26\lib\release" gvc.lib graph.lib cdt.lib pathplan.lib I've been following this tutorial that explains how to use Graphviz as a library, so I linked to the .lib files that it listed.

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  • scheme struct question

    - by qzar
    ;; definition of the structure "book" ;; author: string - the author of the book ;; title: string - the title of the book ;; genre: symbol - the genre (define-struct book (author title genre)) (define lotr1 (make-book "John R. R. Tolkien" "The Fellowship of the Ring" 'Fantasy)) (define glory (make-book "David Brin" "Glory Season" 'ScienceFiction)) (define firstFamily (make-book "David Baldacci" "First Family" 'Thriller)) (define some-books (list lotr1 glory firstFamily)) ;; count-books-for-genre: symbol (list of books) -> number ;; the procedure takes a symbol and a list of books and produces the number ;; of books from the given symbol and genre ;; example: (count-books-for-genre 'Fantasy some-books) should produce 1 (define (count-books-for-genre genre lob) (if (empty? lob) 0 (if (symbol=? (book-genre (first lob)) genre) (+ 1 (count-books-for-genre (rest lob) genre)) (count-books-for-genre (rest lob) genre) ) ) ) (count-books-for-genre 'Fantasy some-books) It produce following exception first: expected argument of type non-empty list; given 'Fantasy, I don't understand whats the problem. Can somebody give me some explanation ? Thank you very much !

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  • Trouble with __VA_ARGS__

    - by Noah Roberts
    C++ preprocessor __VA_ARGS__ number of arguments The accepted answer there doesn't work for me. I've tried with MSVC++ 10 and g++ 3.4.5. I also crunched the example down into something smaller and started trying to get some information printed out to me in the error: template < typename T > struct print; #include <boost/mpl/vector_c.hpp> #define RSEQ_N 10,9,8,7,6,5,4,3,2,1,0 #define ARG_N(_1,_2,_3,_4,_5,_6,_7,_8,_9,_10,N,...) N #define ARG_N_(...) ARG_N(__VA_ARGS__) #define XXX 5,RSEQ_N #include <iostream> int main() { print< boost::mpl::vector_c<int, ARG_N_( XXX ) > > g; // ARG_N doesn't work either. } It appears to me that the argument for ARG_N ends up being 'XXX' instead of 5,RSEQ_N and much less 5,10,...,0. The error output of g++ more specifically says that only one argument is supplied. Having trouble believing that the answer would be proposed and then accepted when it totally fails to work, so what am I doing wrong? Why is XXX being interpreted as the argument and not being expanded? In my own messing around everything works fine until I try to pass off VA_ARGS to a macro containing some names followed by ... like so: #define WTF(X,Y,...) X , Y , __VA_ARGS__ #define WOT(...) WTF(__VA_ARGS__) WOT(52,2,5,2,2) I've tried both with and without () in the various macros that take no input.

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  • Objective-C protocol vs inheritance vs extending?

    - by ryanjm.mp
    I have a couple classes that have nearly identical code. Only a string or two is different between them. What I would like to do is to make them "x" from another class that defines those functions and then uses constants or something else to define those strings that are different. I'm not sure if "x" is inheritance or extending or what. That is what I need help with. For example: objectA.m: -(void)helloWorld { NSLog("Hello %@",child.name); } objectBob.m: #define name @"Bob" objectJoe.m #define name @"Joe" (I'm not sure if it's legal to define strings, but this gets the point across) It would be ideal if objectBob.m and objectJoe.m didn't have to even define the methods, just their relationship to objectA.m. Is there any way to do something like this? It is kind of like protocol, except in reverse, I want the "protocol" to actually define the functions. If all else fails I'll just make objectA.m: -(void)helloWorld:(NSString *name) { NSLog("Hello %@",name); } And have the other files call that function (and just #import objectA.m).

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  • How to Make a Game like Space Invaders - Ray Wenderlich (why do my space invaders scroll off screen)

    - by Erv Noel
    I'm following this tutorial(http://www.raywenderlich.com/51068/how-to-make-a-game-like-space-invaders-with-sprite-kit-tutorial-part-1) and I've run into a problem right after the part where I add [self determineInvaderMovementDirection]; to my GameScene.m file (specifically to my moveInvadersForUpdate method) The tutorial states that the space invaders should be moving accordingly after adding this piece of code but when I run they move to the left and they do not come back. I'm not sure what I am doing wrong as I have followed this tutorial very carefully. Any help or clarification would be greatly appreciated. Thanks in advance ! Here is the full GameScene.m #import "GameScene.h" #import <CoreMotion/CoreMotion.h> #pragma mark - Custom Type Definitions /* The type definition and constant definitions 1,2,3 take care of the following tasks: 1.Define the possible types of invader enemies. This can be used in switch statements later when things like displaying different sprites images for each enemy type. The typedef makes InvaderType a formal Obj-C type that is type checked for method arguments and variables.This is so that the wrong method argument is not used or assigned to the wrong variable. 2. Define the size of the invaders and that they'll be laid out in a grid of rows and columns on the screen. 3. Define a name that will be used to identify invaders when searching for them. */ //1 typedef enum InvaderType { InvaderTypeA, InvaderTypeB, InvaderTypeC } InvaderType; /* Invaders move in a fixed pattern: right, right, down, left, down, right right. InvaderMovementDirection tracks the invaders' progress through this pattern */ typedef enum InvaderMovementDirection { InvaderMovementDirectionRight, InvaderMovementDirectionLeft, InvaderMovementDirectionDownThenRight, InvaderMovementDirectionDownThenLeft, InvaderMovementDirectionNone } InvaderMovementDirection; //2 #define kInvaderSize CGSizeMake(24,16) #define kInvaderGridSpacing CGSizeMake(12,12) #define kInvaderRowCount 6 #define kInvaderColCount 6 //3 #define kInvaderName @"invader" #define kShipSize CGSizeMake(30, 16) //stores the size of the ship #define kShipName @"ship" // stores the name of the ship stored on the sprite node #define kScoreHudName @"scoreHud" #define kHealthHudName @"healthHud" /* this class extension allows you to add “private” properties to GameScene class, without revealing the properties to other classes or code. You still get the benefit of using Objective-C properties, but your GameScene state is stored internally and can’t be modified by other external classes. As well, it doesn’t clutter the namespace of datatypes that your other classes see. This class extension is used in the method didMoveToView */ #pragma mark - Private GameScene Properties @interface GameScene () @property BOOL contentCreated; @property InvaderMovementDirection invaderMovementDirection; @property NSTimeInterval timeOfLastMove; @property NSTimeInterval timePerMove; @end @implementation GameScene #pragma mark Object Lifecycle Management #pragma mark - Scene Setup and Content Creation /*This method simply invokes createContent using the BOOL property contentCreated to make sure you don’t create your scene’s content more than once. This property is defined in an Objective-C Class Extension found near the top of the file()*/ - (void)didMoveToView:(SKView *)view { if (!self.contentCreated) { [self createContent]; self.contentCreated = YES; } } - (void)createContent { //1 - Invaders begin by moving to the right self.invaderMovementDirection = InvaderMovementDirectionRight; //2 - Invaders take 1 sec for each move. Each step left, right or down // takes 1 second. self.timePerMove = 1.0; //3 - Invaders haven't moved yet, so set the time to zero self.timeOfLastMove = 0.0; [self setupInvaders]; [self setupShip]; [self setupHud]; } /* Creates an invade sprite of a given type 1. Use the invadeType parameterr to determine color of the invader 2. Call spriteNodeWithColor:size: of SKSpriteNode to alloc and init a sprite that renders as a rect of the given color invaderColor with size kInvaderSize */ -(SKNode*)makeInvaderOfType:(InvaderType)invaderType { //1 SKColor* invaderColor; switch (invaderType) { case InvaderTypeA: invaderColor = [SKColor redColor]; break; case InvaderTypeB: invaderColor = [SKColor greenColor]; break; case InvaderTypeC: invaderColor = [SKColor blueColor]; break; } //2 SKSpriteNode* invader = [SKSpriteNode spriteNodeWithColor:invaderColor size:kInvaderSize]; invader.name = kInvaderName; return invader; } -(void)setupInvaders { //1 - loop over the rows CGPoint baseOrigin = CGPointMake(kInvaderSize.width / 2, 180); for (NSUInteger row = 0; row < kInvaderRowCount; ++row) { //2 - Choose a single InvaderType for all invaders // in this row based on the row number InvaderType invaderType; if (row % 3 == 0) invaderType = InvaderTypeA; else if (row % 3 == 1) invaderType = InvaderTypeB; else invaderType = InvaderTypeC; //3 - Does some math to figure out where the first invader // in the row should be positioned CGPoint invaderPosition = CGPointMake(baseOrigin.x, row * (kInvaderGridSpacing.height + kInvaderSize.height) + baseOrigin.y); //4 - Loop over the columns for (NSUInteger col = 0; col < kInvaderColCount; ++col) { //5 - Create an invader for the current row and column and add it // to the scene SKNode* invader = [self makeInvaderOfType:invaderType]; invader.position = invaderPosition; [self addChild:invader]; //6 - update the invaderPosition so that it's correct for the //next invader invaderPosition.x += kInvaderSize.width + kInvaderGridSpacing.width; } } } -(void)setupShip { //1 - creates ship using makeShip. makeShip can easily be used later // to create another ship (ex. to set up more lives) SKNode* ship = [self makeShip]; //2 - Places the ship on the screen. In SpriteKit the origin is at the lower //left corner of the screen. The anchorPoint is based on a unit square with (0, 0) at the lower left of the sprite's area and (1, 1) at its top right. Since SKSpriteNode has a default anchorPoint of (0.5, 0.5), i.e., its center, the ship's position is the position of its center. Positioning the ship at kShipSize.height/2.0f means that half of the ship's height will protrude below its position and half above. If you check the math, you'll see that the ship's bottom aligns exactly with the bottom of the scene. ship.position = CGPointMake(self.size.width / 2.0f, kShipSize.height/2.0f); [self addChild:ship]; } -(SKNode*)makeShip { SKNode* ship = [SKSpriteNode spriteNodeWithColor:[SKColor greenColor] size:kShipSize]; ship.name = kShipName; return ship; } -(void)setupHud { //Sets the score label font to Courier SKLabelNode* scoreLabel = [SKLabelNode labelNodeWithFontNamed:@"Courier"]; //1 - Give the score label a name so it becomes easy to find later when // the score needs to be updated. scoreLabel.name = kScoreHudName; scoreLabel.fontSize = 15; //2 - Color the score label green scoreLabel.fontColor = [SKColor greenColor]; scoreLabel.text = [NSString stringWithFormat:@"Score: %04u", 0]; //3 - Positions the score label near the top left corner of the screen scoreLabel.position = CGPointMake(20 + scoreLabel.frame.size.width/2, self.size.height - (20 + scoreLabel.frame.size.height/2)); [self addChild:scoreLabel]; //Applies the font of the health label SKLabelNode* healthLabel = [SKLabelNode labelNodeWithFontNamed:@"Courier"]; //4 - Give the health label a name so it can be referenced later when it needs // to be updated to display the health healthLabel.name = kHealthHudName; healthLabel.fontSize = 15; //5 - Colors the health label red healthLabel.fontColor = [SKColor redColor]; healthLabel.text = [NSString stringWithFormat:@"Health: %.1f%%", 100.0f]; //6 - Positions the health Label on the upper right hand side of the screen healthLabel.position = CGPointMake(self.size.width - healthLabel.frame.size.width/2 - 20, self.size.height - (20 + healthLabel.frame.size.height/2)); [self addChild:healthLabel]; } #pragma mark - Scene Update - (void)update:(NSTimeInterval)currentTime { //Makes the invaders move [self moveInvadersForUpdate:currentTime]; } #pragma mark - Scene Update Helpers //This method will get invoked by update -(void)moveInvadersForUpdate:(NSTimeInterval)currentTime { //1 - if it's not yet time to move, exit the method. moveInvadersForUpdate: // is invoked 60 times per second, but you don't want the invaders to move // that often since the movement would be too fast to see if (currentTime - self.timeOfLastMove < self.timePerMove) return; //2 - Recall that the scene holds all the invaders as child nodes; which were // added to the scene using addChild: in setupInvaders identifying each invader // by its name property. Invoking enumerateChildNodesWithName:usingBlock only loops over the invaders because they're named kInvaderType; which makes the loop skip the ship and the HUD. The guts og the block moves the invaders 10 pixels either right, left or down depending on the value of invaderMovementDirection [self enumerateChildNodesWithName:kInvaderName usingBlock:^(SKNode *node, BOOL *stop) { switch (self.invaderMovementDirection) { case InvaderMovementDirectionRight: node.position = CGPointMake(node.position.x - 10, node.position.y); break; case InvaderMovementDirectionLeft: node.position = CGPointMake(node.position.x - 10, node.position.y); break; case InvaderMovementDirectionDownThenLeft: case InvaderMovementDirectionDownThenRight: node.position = CGPointMake(node.position.x, node.position.y - 10); break; InvaderMovementDirectionNone: default: break; } }]; //3 - Record that you just moved the invaders, so that the next time this method is invoked (1/60th of a second from when it starts), the invaders won't move again until the set time period of one second has elapsed. self.timeOfLastMove = currentTime; //Makes it so that the invader movement direction changes only when the invaders are actually moving. Invaders only move when the check on self.timeOfLastMove passes (when conditional expression is true) [self determineInvaderMovementDirection]; } #pragma mark - Invader Movement Helpers -(void)determineInvaderMovementDirection { //1 - Since local vars accessed by block are default const(means they cannot be changed), this snippet of code qualifies proposedMovementDirection with __block so that you can modify it in //2 __block InvaderMovementDirection proposedMovementDirection = self.invaderMovementDirection; //2 - Loops over the invaders in the scene and refers to the block with the invader as an argument [self enumerateChildNodesWithName:kInvaderName usingBlock:^(SKNode *node, BOOL *stop) { switch (self.invaderMovementDirection) { case InvaderMovementDirectionRight: //3 - If the invader's right edge is within 1pt of the right edge of the scene, it's about to move offscreen. Sets proposedMovementDirection so that the invaders move down then left. You compare the invader's frame(the frame that contains its content in the scene's coordinate system) with the scene width. Since the scene has an anchorPoint of (0,0) by default and is scaled to fill it's parent view, this comparison ensures you're testing against the view's edges. if (CGRectGetMaxX(node.frame) >= node.scene.size.width - 1.0f) { proposedMovementDirection = InvaderMovementDirectionDownThenLeft; *stop = YES; } break; case InvaderMovementDirectionLeft: //4 - If the invader's left edge is within 1 pt of the left edge of the scene, it's about to move offscreen. Sets the proposedMovementDirection so invaders move down then right if (CGRectGetMinX(node.frame) <= 1.0f) { proposedMovementDirection = InvaderMovementDirectionDownThenRight; *stop = YES; } break; case InvaderMovementDirectionDownThenLeft: //5 - If invaders are moving down then left, they already moved down at this point, so they should now move left. proposedMovementDirection = InvaderMovementDirectionLeft; *stop = YES; break; case InvaderMovementDirectionDownThenRight: //6 - if the invaders are moving down then right, they already moved down so they should now move right. proposedMovementDirection = InvaderMovementDirectionRight; *stop = YES; break; default: break; } }]; //7 - if the proposed invader movement direction is different than the current invader movement direction, update the current direction to the proposed direction if (proposedMovementDirection != self.invaderMovementDirection) { self.invaderMovementDirection = proposedMovementDirection; } } #pragma mark - Bullet Helpers #pragma mark - User Tap Helpers #pragma mark - HUD Helpers #pragma mark - Physics Contact Helpers #pragma mark - Game End Helpers @end

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