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  • Sqlite3 INSERT INTO Question × 377

    - by user316717
    Hi, My 1st post. I am creating an exercise app that will record the weight used and the number of "reps" the user did in 4 "Sets" per day over a period of 7 days so the user may view their progress. I have built the database table named FIELDS with 2 columns ROW and FIELD_DATA and I can use the code below to load the data into the db. But the code has a sql statement that says, INSERT OR REPLACE INTO FIELDS (ROW, FIELD_DATA)VALUES (%d, '%@'); When I change the statment to: INSERT INTO FIELDS (ROW, FIELD_DATA)VALUES (%d, '%@'); Nothing happens. That is no data is recorded in the db. Below is the code: #define kFilname @"StData.sqlite3" - (NSString *)dataFilePath { NSArray *paths = NSSearchPathForDirectoriesInDomains (NSDocumentDirectory, NSUserDomainMask, YES); NSString *documentsDirectory = [paths objectAtIndex:0]; return [documentsDirectory stringByAppendingPathComponent:kFilname]; } -(IBAction)saveData:(id)sender; { for (int i = 1; i <= 8; i++) { NSString *fieldName = [[NSString alloc]initWithFormat:@"field%d", i]; UITextField *field = [self valueForKey:fieldName]; [fieldName release]; NSString *insert = [[NSString alloc] initWithFormat: @"INSERT OR REPLACE INTO FIELDS (ROW, FIELD_DATA) VALUES (%d, '%@');",i, field.text]; // sqlite3_stmt *stmt; char *errorMsg; if (sqlite3_exec (database, [insert UTF8String], NULL, NULL, &errorMsg) != SQLITE_OK) { // NSAssert1(0, @"Error updating table: %s", errorMsg); sqlite3_free(errorMsg); } } sqlite3_close(database); } So how do I modify the code to do what I want? It seemed like a simple sql statement change at first but obviously there must be more. I am new to Objective-C and iPhone programming. I am not new to using sql statements as I have been creating web apps in ASP for a number of years. Any help will be greatly appreciated, this is driving me nuts! Thanks in advance Dave

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  • Implementing an iterator over binary tree using C++ 11

    - by user1459339
    I would like to create an iterator over the binary tree so as to be able to use range-based for loop. I understand I ought to implement the begin() and end() function first. Begin should probably point to the root. According to the specification, however, the end() functions returns "the element following the last valid element". Which element (node) is that? Would it not be illegal to point to some "invalid" place? The other thing is the operator++. What is the best way to return "next" element in tree? I just need some advice to begin with this programming.

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  • C# Reflection StackTrack get value

    - by John
    I'm making pretty heavy use of reflection in my current project to greatly simplify communication between my controllers and the wcf services. What I want to do now is to obtain a value from the Session within an object that has no direct access to HttpSessionStateBase (IE: Not a controller). For example, a ViewModel. I could pass it in or pass a reference to it etc. but that is not optimal in my situation. Since everything comes from a Controller at some point in my scenario I can do the following to walk the sack to the controller where the call originated, pretty simple stuff: var trace = new System.Diagnostics.StackTrace(); foreach (var frame in trace.GetFrames()) { var type = frame.GetMethod().DeclaringType; var prop = type.GetProperty("Session"); if(prop != null) { // not sure about this part... var value = prop.GetValue(type, null); break; } } The trouble here is that I can't seem to work out how to get the "instance" of the controller or the Session property so that I can read from it.

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  • Memory Barrier by lock statement

    - by jalalaldeen
    I read recently about memory barrier and the reordaring issue and now I have some confusion about it. Let us have a following senario: private object _object1 = null; private object _object2 = null; private bool _usingObject1 = false; private object MyObject { get { if (_usingObject1) { return _object1; } else { return _object2; } } set { if (_usingObject1) { _object1 = value; } else { _object2 = value; } } } private void Update() { _usingMethod1 = true; SomeProperty = FooMethod(); //.. _usingMethod1 = false; } 1- At Update method; is it always _usingMethod1 = true statement excecuted before getting or setting the property? or due reordaring issue we can not garantee that? 2- Should we use volitle like. private volitle bool _usingMethod1 = false; 3- If we use lock; can we garantee then every statement within the lock will be excecuted in order like: private void FooMethod() { object locker = new object(); lock (locker) { x = 1; y = a; i++; } } Thanks in advanced..

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  • Java: GatheringByteChannel advantages?

    - by Jason S
    I'm wondering when the GatheringByteChannel's write methods (taking in an array of ByteBuffers) have advantages over the "regular" WritableByteChannel write methods. I tried a test where I could use the regular vs. the gathering write method on a FileChannel, with approx 400KB/sec total in ByteBuffers of between 23-27 bytes in length in both cases. Gathering writes used an array of 64. The regular method used up approx 12% of my CPU, and the gathering method used up approx 16% of my CPU (worse than the regular method!) This tells me it's NOT useful to use gathering writes on a FileChannel around this range of operating parameters. Why would this be the case, and when would you ever use GatheringByteChannel? (on network I/O?) Relevant differences here: public void log(Queue<Packet> packets) throws IOException { if (this.gather) { int Nbuf = 64; ByteBuffer[] bbufs = new ByteBuffer[Nbuf]; int i = 0; Packet p; while ((p = packets.poll()) != null) { bbufs[i++] = p.getBuffer(); if (i == Nbuf) { this.fc.write(bbufs); i = 0; } } if (i > 0) { this.fc.write(bbufs, 0, i); } } else { Packet p; while ((p = packets.poll()) != null) { this.fc.write(p.getBuffer()); } } }

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  • C# keyhook question

    - by user203123
    I copied the following code from http://www.codeproject.com/KB/cs/CSLLKeyboardHook.aspx, public int hookProc(int code, int wParam, ref keyboardHookStruct lParam) { if (code >= 0) { Keys key = (Keys)lParam.vkCode; if (HookedKeys.Contains(key)) { KeyEventArgs kea = new KeyEventArgs(key); if((wParam == WM_KEYDOWN || wParam == WM_SYSKEYDOWN) && (KeyDown != null)) {KeyDown(this, kea) ;} else if ((wParam == WM_KEYUP || wParam == WM_SYSKEYUP) && (KeyUp != null)) {KeyUp(this, kea); } if (kea.Handled) {return 1;} } } lParam.vkCode ++; lParam.scanCode ++; return CallNextHookEx(hhook, code, wParam, ref lParam); } It works fine but when I make a little change: lParam.vkCode ++; or lParam.scanCode ++; right before the return CallNextHookEx(...), the original keys still appears in Notepad. Ex. If I press "a", I expect the letter in Notepad will be "b" but it still "a". It seems like "lParam" doesn't change. Couldn't understand why?

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  • typedef to store pointers in C

    - by seriouslion
    The Size of pointer depends on the arch of the machine. So sizeof(int*)=sizeof(int) or sizeof(int*)=sizeof(long int) I want to have a custom data type which is either int or long int depending on the size of pointer. I tried to use macro #if, but the condition for macros does not allow sizeof operator. Also when using if-else, typedef is limited to the scope of if. if((sizeof(int)==sizeof(int *)){ typedef int ptrtype; } else{ typedef long int ptrtype; } //ptrtype not avialble here Is there any way to define ptrtype globally?

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  • JQuery 1.3.1 doesn't find dynamically generated rows

    - by Bamelis Steve
    I have just installed in the ASP.NET MVC RC2 and with that also using the JQuery 1.3.1 library. Before I was using the 1.2.6 library. Our application works fine under that library. But now I have strange problem. We have a grid view that we build up with the result of an AJAX call. With the result returned we add new rows to a table through cloning a hidden row. The generated HTML from the JQuery is placing extra parameters to the tags. These are in the form of JQuery12345678="null". They all have the same name. In the head of the table there is a checkbox that selects/unselects all the rows of the table. This by iterating through the rows of the table. $("#selectAllCheckbox").click(function() { var checked = this.checked; $("#dgNewTasks tbody tr").find(':input[type="checkbox"]').each(function() { this.checked = checked; }); }); Now by using the new library the check box are no longer set. I have used IE Developer Tools to check the HTML. If I remove the JQuery12345678="null" parameter from my rows. It works fine. Could someone tell me what I have to do?

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  • Javascript dynamic table memory usage

    - by Dan
    I use a dynamic table: <html> <body> <button id="button">Build table</button> <div id="container"> <script type="text/javascript"> window.onload=function(){ var table = null; var row = "<tr><td>111111111111111111111111111111111111111111111111111111</td>" + "<td>222222222222222222222222222222222222222222222222222222</td>" + "<td>333333333333333333333333333333333333333333333333333333</td></tr>"; var data = null; for (var i = 0; i < 2000; i++){ data += row; } var obj = document.getElementById("button"); obj.onclick=function buildTable(){ document.getElementById("container").innerHTML = "<div><table><tbody>" + data + "</tbody></table></div>"; }; }; </script> </body> </html> Using chromes task manager, each time new data is loaded the memory usage increases considerably and doesn't go down, so after some time the app consumes a lot of memory and requires the browser to be closed. Is there any change in the code I can use to solve this or is it a browser side problem?

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  • How should a multi-threaded C application handle a failed malloc()?

    - by user294463
    A part of an application I'm working on is a simple pthread-based server that communicates over a TCP/IP socket. I am writing it in C because it's going to be running in a memory constrained environment. My question is: what should the program do if one of the threads encounters a malloc() that returns NULL? Possibilities I've come up with so far: No special handling. Let malloc() return NULL and let it be dereferenced so that the whole thing segfaults. Exit immediately on a failed malloc(), by calling abort() or exit(-1). Assume that the environment will clean everything up. Jump out of the main event loop and attempt to pthread_join() all the threads, then shut down. The first option is obviously the easiest, but seems very wrong. The second one also seems wrong since I don't know exactly what will happen. The third option seems tempting except for two issues: first, all of the threads need not be joined back to the main thread under normal circumstances and second, in order to complete the thread execution, most of the remaining threads will have to call malloc() again anyway. What shall I do?

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  • C++ template specialization

    - by user231536
    I have a class template <typename T> class C { static const int K=1; static ostream& print(ostream& os, const T& t) { return os << t;} }; I would like to specialize C for int. //specialization for int template <> C<int>{ static const int K=2; } I want the default print method that works for int to remain and just change the constant. For some specializations, I want to keep K=1 and change the print method because there is no << operator. How do I do this?

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  • Program that edits string and prints each word individually with C

    - by Michael_19
    I keep getting the error segmentation fault (core dumped) when I run my progam. #include<stdio.h> #include<stdlib.h> int nextword(char *str); int main(void) { char str[] = "Hello! Today is a beautiful day!!\t\n"; int i = nextword(str); while(i != -1) { printf("%s\n",&(str[i])); i = nextword(NULL); } return 0; } int nextword(char *str) { // create two static variables - these stay around across calls static char *s; static int nextindex; int thisindex; // reset the static variables if (str != NULL) { s = str; thisindex = 0; // TODO: advance this index past any leading spaces while (s[thisindex]=='\n' || s[thisindex]=='\t' || s[thisindex]==' ' ) thisindex++; } else { // set the return value to be the nextindex thisindex = nextindex; } // if we aren't done with the string... if (thisindex != -1) { nextindex = thisindex; // TODO: two things // 1: place a '\0' after the current word // 2: advance nextindex to the beginning // of the next word while (s[nextindex] != ' ' && s[nextindex] != '\0') nextindex++; str[nextindex] = '\0'; nextindex++; } return thisindex; } The goal of the program is to print each word in the string str[] to the console on a new line. I am a beginning programmer and this is an assignment so I must use this type of format (no string library allowed). I just would like to know where I went wrong and how I can fix it.

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  • Ajax Code to run PHP query After Facebook Like Button is Clicked

    - by John
    I have the PHP below on a file called fblike.php. On another file, I have the Facebook Like button. The Like button functions. I would like to run the code below when the Facebook Like button is clicked. I know that FB.Event.subscribe('edge.create', function(response) {} is supposed to run whenever the Like button is clicked. I know that I am probably supposed to use Javascript and maybe Ajax to cause the PHP on fblike.php to run. But after multiple tries, I can't get it to work. What is the specific Ajax code that I could include within the Facebook Event? Do I need to do anything to the Like button code to allow the Facebook Event to work? $submissionid = $_POST['submissionid']; $uid = $_POST['uid']; mysql_connect("server", "username", "password") or die(mysql_error()); mysql_select_db("database") or die(mysql_error()); $q = "INSERT INTO fblikes VALUES (NULL, '$submissionid', '$uid', NULL)"; $r = mysql_query($q); if($r) { echo "Success!"; } elseif(!$r) { echo "Failed!"; }

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  • Can't compile std::map sorting, why?

    - by Vincenzo
    This is my code: map<string, int> errs; struct Compare { bool operator() (map<string, int>::const_iterator l, map<string, int>::const_iterator r) { return ((*l).second < (*r).second); } } comp; sort(errs.begin(), errs.end(), comp); Can't compile. This is what I'm getting: no matching function for call to ‘sort(..’ Why so? Can anyone help? Thanks!

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  • The Cash or Credit problem

    - by Josh K
    If you go to a store and ask "Cash or Credit?" they might simply say "Yes." This doesn't tell you anything as you posed an OR statement. if(cash || credit) With humans it's possible that they might respond "Both" to that question, or "Only {cash | credit}." Is there a way (or operator) to force the a statement to return the TRUE portions of a statement? For example: boolean cash = true; boolean credit = true; boolean cheque = false; if(cash || credit || cheque ) { // In here you would have an array with cash and credit in it because both of those are true }

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  • binary number comparison

    - by EquinoX
    If I have a 32 bit two's complement number and I want to know what is the easiest way to know of two numbers are equal... what would be the fastest bitwise operator to know this? I know xor'ing both numbers and check if the results are zero works well... any other one's? how about if a number is greater than 0?? I can check the 31'st bit to see if it's greater or equal to 0..but how about bgtz?

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  • EMSA_PSS_ENCODE with libssl

    - by luiss
    Hi I'm trying to use libssl to get some EMSA_PSS_ENCRODING through the function RSA_padding_add_PKCS1_type1 in libssl, but I can't find nor docs nor solutions, so this is the example code I've written: #include <stdio.h> #include <stdlib.h> #include <string.h> #include <openssl/rsa.h> #include <openssl/err.h> FILE *error_file; int main() { int lSize; const unsigned char *string1= (unsigned char *)"The pen is on the table"; unsigned char *stringa=NULL; int num = 64; if ((stringa = (unsigned char *)OPENSSL_malloc(num)) == NULL) fprintf(stderr,"OPENSSL_malloc error\n"); fprintf(stdout,"string1 len is %u\n",lSize); if(RSA_padding_add_PKCS1_type_1(stringa,num,string1,lSize) != 1) fprintf(stderr,"Error: RSA_PADDING error\n"); error_file = fopen("libssl.log", "w"); ERR_print_errors_fp(error_file); fclose(error_file); fprintf(stdout,(char *)stringa); fprintf(stdout,"\n"); } The problem is that I get no output in stringa, I think the function RSA_padding_add.. should be initialized, but I can't find how to do it in the few doc at the openssl site. Thanks

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  • What is the difference between "a is b" and "id(a) == id(b)" in Python?

    - by bp
    The id() inbuilt function gives... an integer (or long integer) which is guaranteed to be unique and constant for this object during its lifetime. The is operator, instead, gives... object identity So why is it possible to have two objects that have the same id but return False to an is check? Here is an example: >>> class Test(): ... def test(): ... pass >>> a = Test() >>> b = Test() >>> id(a.test) == id(b.test) True >>> a.test is b.test False A more troubling example: (continuing the above) >>> b = a >>> b is a True >>> b.test is a.test False >>> a.test is a.test False

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  • MySQL Table Loop using PHP

    - by JM4
    I have an online form which collects consumer data and stores in a dedicated MySQL database. In some instances, data is passed in the URL under the "RefID" variable which is also stored in the database and attached to each registration. I use the 'mysql_num_rows ($result)' to fetch all agent details on another page but this only returns ALL available details. My goal is as follows: GOAL I want to create an HTML table in which rows are automatically generated based on the list of all registrations on my site. A new row is created IF and ONLY IF a unique RefID is present on that particular record. In the event the field is NULL, it is reported on a single line. In short, the HTML table could look something like this: RefID - Number of Enrollments abc123 - 10 baseball - 11 twonk - 7 NULL - 33 Where abc123 is a particular RefID and 10 is the number of times that RefID appears in the DB. If a new registration comes in with RefID = "horses", a new row is created, showing "horses - 1". The HTML table will be viewable by account administrators needing to see the number of enrollments for a particular RefID (which they won't know ahead of time). Anybody have any suggestions?

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  • PHP function to handle most database queries has a problem with results. I am getting the right numb

    - by asdasds
    Here is my little function. It does not handle the results correctly. I do get all the rows that I want, but all the rows of the $results array contain the exact same values. So i make 2 arrays, a temporary array to hold the values after each fetch, and another array to hold all the temporary arrays. First i take the temp array and map its keys to the column names. Then i give it to bind_result, and call fetch() and use it like I would any other result value. Could this be because I re-use the $results array? numresults is the number of values you are taking from each row. if 0, you are not getting any results back. function db_query($db, $query, $params = NULL, $numresults = 0) { if($stmt = $db -> prepare($query)) { if($params != NULL) { call_user_func_array(array($stmt, 'bind_param'), $params); } if(!$stmt -> execute()) { //echo 'exec error:',$db->error; return false; } if($numresults > 0) { $results = array(); $tmpresult = array(); $meta = $stmt->result_metadata(); while ($columnName = $meta->fetch_field()) $tmpresult[] = &$results[$columnName->name]; call_user_func_array(array($stmt, 'bind_result'), $tmpresult); $meta->close(); $results = array(); while($stmt -> fetch()) $results[] = $tmpresult; } $stmt -> close(); } else { //echo 'prepare error: ',$db->error; return false; } if($numresults == 0) return true; return $results; }

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  • Calling a constructor from method within the same class

    - by Nathan
    I'm new to java and I'm learning about creating object classes. One of my homework assignment requires that I call the constructor at least once within a method of the same object class. I'm getting an error that says The method DoubleMatrix(double[][]) is undefined for the type DoubleMatrix Here's my constructor: public DoubleMatrix(double[][] tempArray) { // Declaration int flag = 0; int cnt; // Statement // check to see if doubArray isn't null and has more than 0 rows if(tempArray == null || tempArray.length < 0) { flag++; } // check to see if each row has the same length if(flag == 0) { for(cnt = 0; cnt <= tempArray.length - 1 || flag != 1; cnt++) { if(tempArray[cnt + 1].length != tempArray[0].length) { flag++; } } } else if(flag == 1) { makeDoubMatrix(1, 1);// call makeDoubMatrix method } }// end constructor 2 Here's the method where I try and call the constructor: public double[][] addMatrix(double[][] tempDoub) { // Declaration double[][] newMatrix; int rCnt, cCnt; //Statement // checking to see if both are of same dimension if(doubMatrix.length == tempDoub.length && doubMatrix[0].length == tempDoub[0].length) { newMatrix = new double[doubMatrix.length][doubMatrix[0].length]; // for loop to add matrix to a new one for(rCnt = 0; rCnt <= doubMatrix.length; rCnt++) { for(cCnt = 0; cCnt <= doubMatrix.length; cCnt++) { newMatrix[rCnt][cCnt] = doubMatrix[rCnt][cCnt] + tempDoub[rCnt][cCnt]; } } } else { newMatrix = new double[0][0]; DoubleMatrix(newMatrix) } return newMatrix; }// end addMatrix method Can someone point me to the right direction and explain why I'm getting an error?

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  • [Scala] Using overloaded, typed methods on a collection

    - by stephanos
    I'm quite new to Scala and struggling with the following: I have database objects (type of BaseDoc) and value objects (type of BaseVO). Now there are multiple convert methods (all called 'convert') that take an instance of an object and convert it to the other type accordingly. For example: def convert(doc: ClickDoc): ClickVO = doc match { case null => null case _ => val result = new ClickVO result.x = doc.x result.y = doc.y result } Now I sometimes need to convert a list of objects. How would I do this - I tried: def convert[D <: MyBaseDoc, V <: BaseVO](docs: List[D]):List[V] = docs match { case List() => List() case xs => xs.map(doc => convert(doc)) } Which results in 'overloaded method value convert with alternatives ...'. I tried to add manifest information to it, but couldn't make it work. I couldn't even create one method for each because it'd say that they have the same parameter type after type erasure (List). Ideas welcome!

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  • Double "!!" in Ruby [closed]

    - by Alex Maslakov
    Possible Duplicate: What does !! mean in ruby? Ruby, !! operator (a/k/a the double-bang) Sometimes I see a Ruby code like this def sent? !!@sent_at end It seems to be not logical. Is it necessary to use here double !? As far as I'm concerned, it might be just def sent? @sent_at end UPDATE: then what is the difference between these def sent? !!@sent_at end def sent? @sent_at.nil? end def sent? @sent_at == nil end

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  • Doubt regarding usage of array as a pointer in C

    - by Som
    For eg. I have an array of structs 'a' as below: struct mystruct{ int b int num; }; struct bigger_struct { struct my_struct a[10]; } struct bigger_struct *some_var; i know that the name of an array when used as a value implicitly refers to the address of the first element of the array.(Which is how the array subscript operator works at-least) Can i know do the other way around i.e if i do: some_var->a->b, it should be equivalent to some_var->a[0]->b, am i right? I have tested this and it seems to work , but is this semantically 100% correct?

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  • partial string matching - R

    - by DonDyck
    I need to write a query in R to match partial string in column names. I am looking for something similar to LIKE operator in SQL. For e.g, if I know beginning, middle or end part of the string I would write the query in format: LIKE 'beginning%middle%' in SQL and it would return matching strings. In pmatch or grep it seems I can only specify 'beginning' , 'end' and not the order. Is there any similar function in R that I am looking for? For example, say I am looking in the vector: y<- c("I am looking for a dog", "looking for a new dog", "a dog", "I am just looking") Lets say I want to write a query which picks "looking for a new dog" and I know start of the string is "looking" and end of string is "dog". If I do a grep("dog",y) it will return 1,2,3. Is there any way I can specify beginning and end in grep?

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