Search Results

Search found 4919 results on 197 pages for 'integer'.

Page 70/197 | < Previous Page | 66 67 68 69 70 71 72 73 74 75 76 77  | Next Page >

  • Pass a Delphi class to a C++ function/method that expects a class with __thiscall methods.

    - by Alan G.
    I have some MSVC++ compiled DLL's for which I have created COM-like (lite) interfaces (abstract Delphi classes). Some of those classes have methods that need pointers to objects. These C++ methods are declared with the __thiscall calling convention (which I cannot change), which is just like __stdcall, except a this pointer is passed on the ECX register. I create the class instance in Delphi, then pass it on to the C++ method. I can set breakpoints in Delphi and see it hitting the exposed __stdcall methods in my Delphi class, but soon I get a STATUS_STACK_BUFFER_OVERRUN and the app has to exit. Is it possible to emulate/deal with __thiscall on the Delphi side of things? If I pass an object instantiated by the C++ system then all is good, and that object's methods are called (as would be expected), but this is useless - I need to pass Delphi objects. Edit 2010-04-19 18:12 This is what happens in more detail: The first method called (setLabel) exits with no error (though its a stub method). The second method called (init), enters then dies when it attempts to read the vol parameter. C++ Side #define SHAPES_EXPORT __declspec(dllexport) // just to show the value class SHAPES_EXPORT CBox { public: virtual ~CBox() {} virtual void init(double volume) = 0; virtual void grow(double amount) = 0; virtual void shrink(double amount) = 0; virtual void setID(int ID = 0) = 0; virtual void setLabel(const char* text) = 0; }; Delphi Side IBox = class public procedure destroyBox; virtual; stdcall; abstract; procedure init(vol: Double); virtual; stdcall; abstract; procedure grow(amount: Double); virtual; stdcall; abstract; procedure shrink(amount: Double); virtual; stdcall; abstract; procedure setID(val: Integer); virtual; stdcall; abstract; procedure setLabel(text: PChar); virtual; stdcall; abstract; end; TMyBox = class(IBox) protected FVolume: Double; FID: Integer; FLabel: String; // public constructor Create; destructor Destroy; override; // BEGIN Virtual Method implementation procedure destroyBox; override; stdcall; // empty - Dont need/want C++ to manage my Delphi objects, just call their methods procedure init(vol: Double); override; stdcall; // FVolume := vol; procedure grow(amount: Double); override; stdcall; // Inc(FVolume, amount); procedure shrink(amount: Double); override; stdcall; // Dec(FVolume, amount); procedure setID(val: Integer); override; stdcall; // FID := val; procedure setLabel(text: PChar); override; stdcall; // Stub method; empty. // END Virtual Method implementation property Volume: Double read FVolume; property ID: Integer read FID; property Label: String read FLabel; end; I would have half expected using stdcall alone to work, but something is messing up, not sure what, perhaps something to do with the ECX register being used? Help would be greatly appreciated. Edit 2010-04-19 17:42 Could it be that the ECX register needs to be preserved on entry and restored once the function exits? Is the this pointer required by C++? I'm probably just reaching at the moment based on some intense Google searches. I found something related, but it seems to be dealing with the reverse of this issue.

    Read the article

  • VB .NET Shared Function if called multiple times simultaneously

    - by Mehdi Anis
    Consider I have a shared function:- Public Shared Function CalculateAreaFromRadius(ByVal radius As Double) As Double ' square the radius... Dim radiusSquared As Double radiusSquared = radius * radius ' multiply it by pi... Dim result As Double result = radiusSquared * Math.PI 'Wait a bit, for the sake of testing and 'simulate another call will be made b4 earlier one ended or such for i as Integer = 0 to integer.Max Next ' return the result... Return result End Function My Questions: If I have two or more threads in the same vb .net app and each of them calls the shared function at the same time with different RADIUS, will they each get their own AREA? I want to know for each call to the function if it is using same local variables or each call creates new instances of local variables? Will the answers to above questions be same If I have multiple (2+) single threaded apps and they all call the function at the same time with different RADIUS value? I will appreciate your reponse. Thank you.

    Read the article

  • Single-letter prefix for PHP class constants?

    - by keithjgrant
    I've noticed many (all?) PHP constants have a single-letter prefix, like E_NOTICE, T_STRING, etc. When defining a set of class constants that work in conjunction with one another, do you prefer to follow similar practice, or do you prefer to be more verbose? class Foo { // let's say 'I' means "input" or some other relevant word const I_STRING = 'string'; const I_INTEGER = 'integer'; const I_FLOAT = 'float'; } or class Bar { const INPUT_STRING = 'string'; const INPUT_INTEGER = 'integer'; const INPUT_FLOAT = 'float'; }

    Read the article

  • C# : Number Conversion Problem

    - by Sayem Ahmed
    Today I faced a strange problem in C#. I have an ASP.NET page where user can enter certain price, quantity etc. I get the price value, convert it to double, then multiply it with 100 and then typecast it to an integer. When the price is "33.30", after converting it to double it remains 33.3 (obviously...), but after multiplying it with 100, it becomes 3329.9999999999995, and when I cast it to integer by applying simple cast operator "(int) (price * 100) ", it becomes 3329. Right now I have no idea why this is happening. So I thought may be you guys can help :) .

    Read the article

  • Convert NSData into Hex NSString

    - by Dawson
    With reference to the following question: Convert NSData into HEX NSSString I have solved the problem using the solution provided by Erik Aigner which is: NSData *data = ...; NSUInteger capacity = [data length] * 2; NSMutableString *stringBuffer = [NSMutableString stringWithCapacity:capacity]; const unsigned char *dataBuffer = [data bytes]; NSInteger i; for (i=0; i<[data length]; ++i) { [stringBuffer appendFormat:@"%02X", (NSUInteger)dataBuffer[i]]; } However, there is one small problem in that if there are extra zeros at the back, the string value would be different. For eg. if the hexa data is of a string @"3700000000000000", when converted using a scanner to integer: unsigned result = 0; NSScanner *scanner = [NSScanner scannerWithString:stringBuffer]; [scanner scanHexInt:&result]; NSLog(@"INTEGER: %u",result); The result would be 4294967295, which is incorrect. Shouldn't it be 55 as only the hexa 37 is taken? So how do I get rid of the zeros? EDIT: (In response to CRD) Hi, thanks for clarifying my doubts. So what you're doing is to actually read the 64-bit integer directly from a byte pointer right? However I have another question. How do you actually cast NSData to a byte pointer? To make it easier for you to understand, I'll explain what I did originally. Firstly, what I did was to display the data of the file which I have (data is in hexadecimal) NSData *file = [NSData dataWithContentsOfFile:@"file path here"]; NSLog(@"Patch File: %@",file); Output: Next, what I did was to read and offset the first 8 bytes of the file and convert them into a string. // 0-8 bytes [file seekToFileOffset:0]; NSData *b = [file readDataOfLength:8]; NSUInteger capacity = [b length] * 2; NSMutableString *stringBuffer = [NSMutableString stringWithCapacity:capacity]; const unsigned char *dataBuffer = [b bytes]; NSInteger i; for (i=0; i<[b length]; ++i) { [stringBuffer appendFormat:@"%02X", (NSUInteger)dataBuffer[i]]; } NSLog(@"0-8 bytes HEXADECIMAL: %@",stringBuffer); As you can see, 0x3700000000000000 is the next 8 bytes. The only changes I would have to make to access the next 8 bytes would be to change the value of SeekFileToOffset to 8, so as to access the next 8 bytes of data. All in all, the solution you gave me is useful, however it would not be practical to enter the hexadecimal values manually. If formatting the bytes as a string and then parsing them is not the way to do it, then how do I access the first 8 bytes of the data directly and cast them into a byte pointer?

    Read the article

  • Can this way of storing typed objects be improved?

    - by Pindatjuh
    This is an "can it be improved"-question. Topic: Storing typed objects in memory. Background information: I'm building a compiler for the x86-32 Windows platform for my language. My goal includes typed objects. Idea: Every primitive is a semi-class (it can be used as if it was a normal class, but it's stored more compact). Every class is represented by primitives and some meta-data (containing class-properties, inheritance stuff, etc.). The meta-data is complex: it doesn't use fields but instead context-switches. For primitives, the meta-data is very small, compared to a "real" class, which is alot bigger. This enables another idea that "primitives are objects", in my language, which I found nessecairy. Example: If I have an array of 32 booleans, then the pure content of this array is exactly 4 byte (32 bits of booleans). The meta-data will contain flags that the type is an array of booleans, which contains 32 entries. The meta-data is very compacted, on bit-level: using a sort of "packing" mechanism, which is read by a FSM at runtime, when doing inspection of the type (like when passing the object to methods for checking, etc.) For instance (read from left to right, top to bottom, remember vertical position when going to the right, and check nearest column header for meaning of switch): Primitive? Array? Type-Meta 1 Byte? || Size (1 byte) 1 1 [...] 1 [...] done 0 2 Bytes? || Size (2 bytes) 1 [...] done || Size (4 bytes) 0 [...] done Integer? 1 Byte? 2 Bytes? 0 1 0 1 done 1 done 0 done Boolean? Byte? 0 1 0 done 1 done More-Primitives 0 .... Class-Stuff (Huge) 0 ... (After reaching done the data is inserted. || = byte alignment. [...] is variable sized. ... is not described here, for simplicity. And let's call them cost-based-data-structures.) For an array of 32 booleans containing all true values, the memory for this type would be (read top-down): 1 Primitive 1 Array 1 ArrayType: Primitive 0 Not-Array 0 Not-Integer 1 Boolean 0 Not-Byte (thus bit) 1 Integer Size: 1 Byte 00100000 Array size 01010101 01010101 01010101 01010101 Data (user defined) Thus, 8 bytes represent 32 booleans in an array: 11100101 00100000 01010101 01010101 01010101 01010101 How can I improve this? (Both performance- and memory-consumption wise)

    Read the article

  • Where will this AsyncTask run?

    - by Binoy Babu
    Say I have this code in the AlertDialog.Builder(context) of my application. The question is in which Thread will it run? final Thread myPrettyOperation = new Thread() { @Override public void run() { //Do some really long operation. } }; class MyPrettyTask extends AsyncTask<Void, Integer, Boolean> { protected Boolean doInBackground( Void... voids) { myPrettyOperation.start(); return true; } protected void onProgressUpdate( Integer... progress) { } protected void onPostExecute(Boolean result) { } } new MyPrettyTask().execute();

    Read the article

  • SQL GROUP BY with "default values"

    - by Christoph Schiessl
    I'm trying to create SELECT statement with a GROUP BY clause, which should return "default values". Imagine the following simple MySQL table: CREATE TABLE `tracker` ( `id` INTEGER PRIMARY KEY auto_increment, `date` DATETIME NOT NULL, `customer_id` INTEGER NOT NULL ); The table contains only one record: INSERT INTO `tracker` (`date`, `customer_id`) VALUES('2010-05-03', 1); After wards I'm executing the following SQL query: SELECT DATE(`date`), COUNT(customer_id) FROM tracker WHERE DATE(`date`) >= '2010-05-01' AND DATE(`date`) <= '2010-05-05' GROUP BY DATE(`date`) ORDER BY DATE(`date`); And get the expected result set: +----+---------------------+-------------+ | id | date | customer_id | +----+---------------------+-------------+ | 1 | 2010-05-10 00:00:00 | 1 | +----+---------------------+-------------+ However, I would like the result set to look like this: +--------------+--------------------+ | DATE(`date`) | COUNT(customer_id) | +--------------+--------------------+ | 2010-05-01 | 0 | | 2010-05-02 | 0 | | 2010-05-03 | 1 | | 2010-05-04 | 0 | | 2010-05-05 | 0 | +--------------+--------------------+ Is it possible to achieve this behavior?

    Read the article

  • Conditionally set a column to its default value in Postgres

    - by Evgeny
    I've got a PostgreSQL 8.4 table with an auto-incrementing, but nullable, integer column. I want to update some column values and, if this column is NULL then set it to its default value (which would be an integer auto-generated from a sequence), but I want to return its value in either case. So I want something like this: UPDATE mytable SET incident_id = COALESCE(incident_id, DEFAULT), other = 'somethingelse' WHERE ... RETURNING incident_id Unfortunately, this doesn't work - it seems that DEFAULT is special and cannot be part of an expression. What's the best way to do this?

    Read the article

  • Ruby on Rails and database associations

    - by Marco
    Hi to all, I'm new to the Ruby world, and there is something unclear to me in defining associations between models. The question is: where is the association saved? For example, if i create a Customer model by executing: generate model Customer name:string age:integer and then i create an Order model generate model Order description:text quantity:integer and then i set the association in the following way: class Customer < ActiveRecord::Base has_many :orders end class Order < ActiveRecord::Base belongs_to :customer end I think here is missing something, for example the foreign key between the two entities. How does it handle the associations created with the keywords "has_many" and "belongs_to" ? Thanks

    Read the article

  • MS Access: Order of Events in event ApplyFilter (ADP Project)

    - by Jose Valdes
    I'm having problems with the execution of ServerFilterByForm in Access 2003 When I apply the entered filter it returns the requested data but after it appear on screen (Form) it disappears. Don't know why this is happening Does anyone had the same problem? How can it be solved? Heris is part of the code Private Sub Form_ApplyFilter(Cancel As Integer, ApplyType As Integer) Dim stSql As String If Len(ServerFilter) > 0 Then stSql = "SELECT * FROM v_InitialReviewQuery " & _ " WHERE " + ServerFilter & _ " ORDER BY acctnumber" Else stSql = "SELECT top 1 * FROM v_InitialReviewQuery ORDER BY acctnumber" End If Me.RecordSource = stSql End Sub

    Read the article

  • XdmException on XQSharp XPathEvaluate

    - by Florian
    I am trying to evaluate a XPathExpression with XQSharp and get the Error:"Type check error. The empty sequence cannot be cast to type 'xs:integer'." AltovaXMLSpy evaluates it correct as "true". oXmlDoc.CreateNavigator().XPathEvaluate("root/foo/bar cast as xs:integer lt count(root/blah/blub)", oNamespaseManager).ToString() This XML looks like this: <root xmlns:xs="http://www.w3.org/2001/XMLSchema"> <foo> <bar>0</bar> </foo> <blah> <blub/> </blah> </root> What am I missing?

    Read the article

  • How to set default values to all wrong or null parameters of method?

    - by Roman
    At the moment I have this code (and I don't like it): private RenderedImage private RenderedImage getChartImage (GanttChartModel model, String title, Integer width, Integer height, String xAxisLabel, String yAxisLabel, Boolean showLegend) { if (title == null) { title = ""; } if (xAxisLabel == null) { xAxisLabel = ""; } if (yAxisLabel == null) { yAxisLabel = ""; } if (showLegend == null) { showLegend = true; } if (width == null) { width = DEFAULT_WIDTH; } if (height == null) { height = DEFAULT_HEIGHT; } ... } How can I improve it? I have some thoughts about introducing an object which will contain all these parameters as fields and then, maybe, it'll be possible to apply builder pattern. But still don't have clear vision how to implement that and I'm not sure that it's worth to be done. Any other ideas?

    Read the article

  • Does CLOS have an eql specialization dispatch on strings?

    - by mhb
    Examples of what you can do. (defmethod some-fn ((num real)) (print "an integer")) (defmethod some-fn ((num real)) (print "a real")) (defmethod some-fn ((num (eql 0))) (print "zero")) (some-fn 19323923198319) "an integer" (some-fn 19323923198319.3) "a real" (some-fn 0) "zero" It also works with a general 'string type. (defmethod some-fn ((num string)) (print "a string")) (some-fn "asrt") "a string" Not with a specific string, however (defmethod some-fn ((num (eql "A")) (print "a specifict string"))) => doesn't compile I imagine it doesn't work because eql does not work on strings in the way that would be necessary for it to work. (eql "a" "a") => nil Is there a way to do it?

    Read the article

  • Stuck at being unable to print a substring no more than 4679 characters

    - by Newcoder
    I have a program that does string manipulation on very large strings (around 100K). The first step in my program is to cleanup the input string so that it only contains certain characters. Here is my method for this cleanup: public static String analyzeString (String input) { String output = null; output = input.replaceAll("[-+.^:,]",""); output = output.replaceAll("(\\r|\\n)", ""); output = output.toUpperCase(); output = output.replaceAll("[^XYZ]", ""); return output; } When i print my 'input' string of length 97498, it prints successfully. My output string after cleanup is of length 94788. I can print the size using output.length() but when I try to print this in Eclipse, output is empty and i can see in eclipse output console header. Since this is not my final program, so I ignored this and proceeded to next method that does pattern matching on this 'cleaned-up' string. Here is code for pattern matching: public static List<Integer> getIntervals(String input, String regex) { List<Integer> output = new ArrayList<Integer> (); // Do pattern matching Pattern p1 = Pattern.compile(regex); Matcher m1 = p1.matcher(input); // If match found while (m1.find()) { output.add(m1.start()); output.add(m1.end()); } return output; } Based on this program, i identify the start and end intervals of my pattern match as 12351 and 87314. I tried to print this match as output.substring(12351, 87314) and only get blank output. Numerous hit and trial runs resulted in the conclusion that biggest substring that i can print is of length 4679. If i try 4680, i again get blank input. My confusion is that if i was able to print original string (97498) length, why i couldnt print the cleaned-up string (length 94788) or the substring (length 4679). Is it due to regular expression implementation which may be causing some memory issues and my system is not able to handle that? I have 4GB installed memory.

    Read the article

  • efficient way to detect if an image is empty

    - by Jos
    Hi, I need a very fast method to detect if an image is empty. Im my case then all pixels are white and transparant. The images are png's. My current method is to load them in a memory bitmap and check each pixel value, but this is way to slow. Is there a more efficient way? This is my current code: 'Lock the bitmap bits. Dim bmpData As System.Drawing.Imaging.BitmapData = bmp.LockBits(rectBmp, _ Drawing.Imaging.ImageLockMode.ReadOnly, bmp.PixelFormat) Try Dim x As Integer Dim y As Integer For y = 0 To bmpData.Height - 1 For x = 0 To bmpData.Width - 1 If System.Runtime.InteropServices.Marshal.ReadByte(bmpData.Scan0, (bmpData.Stride * y) + (4 * x) + 3) <> 0 Then Return True Exit For End If Next Next Finally bmp.UnlockBits(bmpData) End Try

    Read the article

  • Problem with Clojure function

    - by Bozhidar Batsov
    Hi, everyone, I've started working yesterday on the Euler Project in Clojure and I have a problem with one of my solutions I cannot figure out. I have this function: (defn find-max-palindrom-in-range [beg end] (reduce max (loop [n beg result []] (if (>= n end) result (recur (inc n) (concat result (filter #(is-palindrom? %) (map #(* n %) (range beg end))))))))) I try to run it like this: (find-max-palindrom-in-range 100 1000) and I get this exception: java.lang.Integer cannot be cast to clojure.lang.IFn [Thrown class java.lang.ClassCastException] which I presume means that at some place I'm trying to evaluate an Integer as a function. I however cannot find this place and what puzzles me more is that everything works if I simply evaluate it like this: (reduce max (loop [n 100 result []] (if (>= n 1000) result (recur (inc n) (concat result (filter #(is-palindrom? %) (map #(* n %) (range 100 1000)))))))) (I've just stripped down the function definition and replaced the parameters with constants) Thanks in advance for your help and sorry that I probably bother you with idiotic mistake on my part. Btw I'm using Clojure 1.1 and the newest SLIME from ELPA.

    Read the article

  • Is there any performance overhead in using RaiseEvent in .net

    - by Sachin
    Is there any performance overhead in using RaiseEvent in .net I have a code which is similar to following. Dim _startTick As Integer = Environment.TickCount 'Do some Task' Dim duration As Integer = Environment.TickCount - _startTick Logger.Debug("Time taken : {0}", duration) RaiseEvent Datareceived() Above code returns Time Taken :1200 Time Taken :1400 But if remove RaiseEvent it returns Time Taken :110 Time Taken :121 I am surprised that the raiseevent is called after the logging of time taken. How it effects total time taken. I am working on Compact framework. Update: In the Eventhandler I had given a MsgBox. When I removed the message box it is now showing time taken as 110,121,etc i.e. less that 500 milliseconds. If I put the Msgbox back in eventhandler it shows 1200,1400,etc i.e. more that a second. More surprised now.(Event is raised after the logging part)

    Read the article

  • Mutual Information / Entropy Calculation Help

    - by Fillip
    Hi, Hoping someone can give me some pointers with this entropy problem. Say X is chosen randomly from the uniform integer distribution 0-32 (inclusive). I calculate the entropy, H(X) = 32 bits, as each Xi has equal probability of occurring. Now, say the following pseudocode executes. int r = rand(0,1); // a random integer 0 or 1 r = r * 33 + X; How would I work out the mutual information between the two variables r and X? Mutual Information is defined as I(X; Y) = H(X) - H(X|Y) but I don't really understand how to apply the conditional entropy H(X|Y) to this problem. Thanks

    Read the article

  • Pascal - bad number format

    - by Donator
    Program: program s; type info = record name, surname: string; min, sek: integer; end; type arrays = array[1..50] of info; var c, b: text; A: arrays; gr_sk, grup_dal: integer; begin assign(c, 'info.txt'); reset(c); read(c, gr_sk); read(c, grup_dal); id := 1; read(c, A[id].name); read(c, A[id].sek); close(c); end. info.txt file: 3 4 yhgf 4 Please, tell me what is wrong with that. It says that it is bad number format for line 19 I guess.

    Read the article

  • Rails 3: habtm migration, primary key issue

    - by Brian Wigginton
    I'm trying to setup a migration file for a habtm relationship, however when I run the migration I'm getting the following error: Primary key is not allowed in a has_and_belongs_to_many join table (parts_vehicles). Here is my migration file (20110111035950_create_parts_vehicles.rb): class CreatePartsVehiclesJoinTable < ActiveRecord::Migration def self.up create_table :parts_vehicles, :id => false do |t| t.integer :part_id t.integer :vehicle_id end end def self.down drop_table :parts_vehicles end end The documentation example states to use :id => false to disable a primary key from being generated, but I'm still getting the error.

    Read the article

  • expand a varchar column very slowly , why?

    - by francs
    Hi We need to modify a column of a big product table , usually normall ddl statments will be excutely fast ,but the above ddl statmens takes about 10 minnutes?I wonder know the reason! I just want to expand a varchar column?The following is the detailsl --table size wapreader_log= select pg_size_pretty(pg_relation_size('log_foot_mark')); pg_size_pretty ---------------- 5441 MB (1 row) --table ddl wapreader_log= \d log_foot_mark Table "wapreader_log.log_foot_mark" Column | Type | Modifiers -------------+-----------------------------+----------- id | integer | not null create_time | timestamp without time zone | sky_id | integer | url | character varying(1000) | refer_url | character varying(1000) | source | character varying(64) | users | character varying(64) | userm | character varying(64) | usert | character varying(64) | ip | character varying(32) | module | character varying(64) | resource_id | character varying(100) | user_agent | character varying(128) | Indexes: "pk_log_footmark" PRIMARY KEY, btree (id) --alter column wapreader_log= \timing Timing is on. wapreader_log= ALTER TABLE wapreader_log.log_foot_mark ALTER column user_agent TYPE character varying(256); ALTER TABLE Time: 603504.835 ms

    Read the article

  • Java CRTP: Works for container but not for methods?

    - by Daniel
    I have a baseclass with a protected static ArrayList. I want to have a seperate ArrayList for each kind of subclass that extends this baseclass. This is when I applied CRTP: public class BaseExample<T> { protected static ArrayList<Integer> data = new ArrayList<Integer>(); } This works just fine. However, when I try to implement the following static method in the same base class, it doesn't adhere to CRTP: public static void clear() { data.clear(); } For example: class SubExample extends BaseExample<SubExample> { // insertion methods accessing 'data' field // these work fine :) } SubExample.clear(); // does not seem to clear data container Do I need to somehow explicitly specify T in my baseclass clear method? Note: These are all pure static classes.

    Read the article

< Previous Page | 66 67 68 69 70 71 72 73 74 75 76 77  | Next Page >