Search Results

Search found 24721 results on 989 pages for 'int tostring'.

Page 439/989 | < Previous Page | 435 436 437 438 439 440 441 442 443 444 445 446  | Next Page >

• forward declare static function c++

  - by Matthew Scouten

  I want to forward declare a static member function of a class in another file. What I WANT to do looks like this: BigMassiveHeader.h: class foo { static void init_foos(); } Main.cpp: class foo; void init_foos(); int main(char** argv, int argc) { foo::init_foos() } This fails out with "error C2027: use of undefined type 'tt_py_ns::foo'" Is there a way to accomplish what I want to do with out making init_foos a free function, or including BigMassiveHeader.h? (BigMassiveHeader.h is noticeably effecting compile time, and is included everywhere.)

  Read the article

• Convert Decimal to ASCII

  - by Dan Snyder

  I'm having difficulty using reinterpret_cast. Before I show you my code I'll let you know what I'm trying to do. I'm trying to get a filename from a vector full of data being used by a MIPS I processor I designed. Basically what I do is compile a binary from a test program for my processor, dump all the hex's from the binary into a vector in my c++ program, convert all of those hex's to decimal integers and store them in a DataMemory vector which is the data memory unit for my processor. I also have instruction memory. So When my processor runs a SYSCALL instruction such as "Open File" my C++ operating system emulator receives a pointer to the beginning of the filename in my data memory. So keep in mind that data memory is full of ints, strings, globals, locals, all sorts of stuff. When I'm told where the filename starts I do the following: Convert the whole decimal integer element that is being pointed to to its ASCII character representation, and then search from left to right to see if the string terminates, if not then just load each character consecutively into a "filename" string. Do this until termination of the string in memory and then store filename in a table. My difficulty is generating filename from my memory. Here is an example of what I'm trying to do: C++ Syntax (Toggle Plain Text) 1.Index Vector NewVector ASCII filename 2.0 240faef0 128123792 'abc7' 'a' 3.0 240faef0 128123792 'abc7' 'ab' 4.0 240faef0 128123792 'abc7' 'abc' 5.0 240faef0 128123792 'abc7' 'abc7' 6.1 1234567a 243225 'k2s0' 'abc7k' 7.1 1234567a 243225 'k2s0' 'abc7k2' 8.1 1234567a 243225 'k2s0' 'abc7k2s' 9. //EXIT LOOP// 10.1 1234567a 243225 'k2s0' 'abc7k2s' Index Vector NewVector ASCII filename 0 240faef0 128123792 'abc7' 'a' 0 240faef0 128123792 'abc7' 'ab' 0 240faef0 128123792 'abc7' 'abc' 0 240faef0 128123792 'abc7' 'abc7' 1 1234567a 243225 'k2s0' 'abc7k' 1 1234567a 243225 'k2s0' 'abc7k2' 1 1234567a 243225 'k2s0' 'abc7k2s' //EXIT LOOP// 1 1234567a 243225 'k2s0' 'abc7k2s' Here is the code that I've written so far to get filename (I'm just applying this to element 1000 of my DataMemory vector to test functionality. 1000 is arbitrary.): C++ Syntax (Toggle Plain Text) 1.int i = 0; 2.int step = 1000;//top->a0; 3.string filename; 4.char *temp = reinterpret_cast<char*>( DataMemory[1000] );//convert to char 5.cout << "a0:" << top->a0 << endl;//pointer supplied 6.cout << "Data:" << DataMemory[top->a0] << endl;//my vector at pointed to location 7.cout << "Data(1000):" << DataMemory[1000] << endl;//the element I'm testing 8.cout << "Characters:" << &temp << endl;//my temporary char array 9. 10.while(&temp[i]!=0) 11.{ 12. filename+=temp[i];//add most recent non-terminated character to string 13. i++; 14. if(i==4)//when 4 chatacters have been added.. 15. { 16. i=0; 17. step+=1;//restart loop at the next element in DataMemory 18. temp = reinterpret_cast<char*>( DataMemory[step] ); 19. } 20. } 21. cout << "Filename:" << filename << endl; int i = 0; int step = 1000;//top-a0; string filename; char *temp = reinterpret_cast( DataMemory[1000] );//convert to char cout << "a0:" << top-a0 << endl;//pointer supplied cout << "Data:" << DataMemory[top-a0] << endl;//my vector at pointed to location cout << "Data(1000):" << DataMemory[1000] << endl;//the element I'm testing cout << "Characters:" << &temp << endl;//my temporary char array while(&temp[i]!=0) { filename+=temp[i];//add most recent non-terminated character to string i++; if(i==3)//when 4 chatacters have been added.. { i=0; step+=1;//restart loop at the next element in DataMemory temp = reinterpret_cast( DataMemory[step] ); } } cout << "Filename:" << filename << endl; So the issue is that when I do the conversion of my decimal element to a char array I assume that 8 hex #'s will give me 4 characters. Why isn't this this case? Here is my output: C++ Syntax (Toggle Plain Text) 1.a0:0 2.Data:0 3.Data(1000):4428576 4.Characters:0x7fff5fbff128 5.Segmentation fault

  Read the article

• MySQL - getting SUM of MAX results from 2 tables

  - by SODA

  Hi, Here's my problem: I have 2 identical tables (past month data, current month data) - data_2010_03, data_2010_04: Content_type (VARCHAR), content_id (INT), month_count (INT), pubDate (DATETIME) Data in month_count is updated hourly, so for each combination of content_type and content_id we insert new row, where value of month_count is incrementally updated. Now I try something like this: SELECT MAX(t1.month_count) AS max_1, MAX(t2.month_count) AS max_2, SUM(max_1 + max_2) AS result, t1.content_type, t1.content_id FROM data_2010_03 AS t1 JOIN data_2010_04 AS t2 ON t1.content_type = t2.content_type AND t1.content_id = t2.content_id WHERE t2.pubDate < '2010-04-08' AND t1.content_type = 'video' GROUP BY t1.content_id ORDER BY result desc, max_1 desc, max_2 desc LIMIT 0,10 I get an error "Unknown column 'max_1' in 'field list'. Please help.

  Read the article

• how to check if internal storage file has any data

  - by user3720291

  public class Save extends Activity { int levels = 2; int data_block = 1024; //char[] data = new char[] {'0', '0'}; String blankval = "0"; String targetval = "0"; String temp; String tempwrite; String string = "null"; TextView tex1; TextView tex2; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.save); Intent intent = getIntent(); Bundle b = intent.getExtras(); tex1 = (TextView) findViewById(R.id.textView1); tex2 = (TextView) findViewById(R.id.textView2); if(b!=null) { string =(String) b.get("string"); } loadprev(); save(); } public void save() { if (string.equals("Blank")) blankval = "1"; if (string.equals("Target")) targetval = "1"; temp = blankval + targetval; try { FileOutputStream fos = openFileOutput("data.gds", MODE_PRIVATE); fos.write(temp.getBytes()); fos.close(); } catch (FileNotFoundException e) {e.printStackTrace();} catch (IOException e) {e.printStackTrace();} tex1.setText(blankval); tex2.setText(targetval); } public void loadprev() { String final_data = ""; try { FileInputStream fis = openFileInput("data.gds"); InputStreamReader isr = new InputStreamReader(fis); char[] data = new char[data_block]; int size; while((size = isr.read(data))>0) { String read_data = String.copyValueOf(data, 0, size); final_data += read_data; data = new char[data_block]; } } catch (FileNotFoundException e) {e.printStackTrace();} catch (IOException e) {e.printStackTrace();} char[] tempread = final_data.toCharArray();; blankval = "" + tempread[0]; targetval = "" + tempread[1]; } } After much tinkering i have finally managed to get my save/load function to work, but it does have an error, pretty much i got it to work then i did a fresh reintall deleting data.gds, afterwards the save/load function crashes because the data.gds file has no previous values. can i use a if statment to check if data.gds has any values in it, if so how do i do it and if not, then what could i use instead?

  Read the article

• C++ Templates: implicit conversion, no matching function for call to ctor

  - by noname

  template<class T> class test { public: test() { } test(T& e) { } }; int main() { test<double> d(4.3); return 0; } Compiled using g++ 4.4.1 with the following errors: g++ test.cpp -Wall -o test.exe test.cpp: In function 'int main()': test.cpp:18: error: no matching function for call to 'test<double>::test(double) ' test.cpp:9: note: candidates are: test<T>::test(T&) [with T = double] test.cpp:5: note: test<T>::test() [with T = double] test.cpp:3: note: test<double>::test(const test<double>&) make: *** [test.exe] Error 1 However, this works: double a=1.1; test<double> d(a); Why is this happing? Is it possible that g++ cannot implicitly convert literal expression 1.1 to double? Thanks.

  Read the article

• WPF: Binding with title and subitems

  - by John

  I am having some issues trying to learn WPF. What I am trying to do is to bind a class that has a string and an array of strings. I would like to bind the string as the title and array as the contents of an expander, but I am having difficulties. What am I missing to make this work? Any help would be appreciated, TIA. This is the code I have thus far: XAML <Window x:Class="WpfApplication1.Window1" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" Title="Window1" Height="300" Width="300"> <Grid> <ListBox Grid.Column="0" Name="lbTopics" ItemsSource="{Binding}"> <ListBox.ItemTemplate> <DataTemplate> <Expander Header="{Binding Path=TopicName}" > <Expander.Content> <ListBox> <ListBox.ItemTemplate> <DataTemplate> <Label Content="{Binding Path=(ItemName)}" Width="120px" Height="32px" Foreground="Black" /> </DataTemplate> </ListBox.ItemTemplate> </ListBox> </Expander.Content> </Expander> </DataTemplate> </ListBox.ItemTemplate> </ListBox> </Grid> C# namespace WpfApplication1 { public partial class Window1 : Window { public Window1() { InitializeComponent(); lbTopics.DataContext = new Topics(); } } public class Topics : ObservableCollection<Topic> { public Topics() { for (int i = 0; i < 10; i++) { this.Add(new Topic(i)); } } } public class Topic { public Topic(int i) { TopicName = "Topic " + i; ItemName = new List<string>(10); for (int j = 0; j < 10; j++) { ItemName.Add(i + " - Item " + j); } } public string TopicName { get; set; } public List<string> ItemName { get; set; } } }

  Read the article

• error in finding out the lexems and no of lines of a text file in C

  - by mekasperasky

  #include<stdio.h> #include<ctype.h> #include<string.h> int main() { int i=0,j,k,lines_count[2]={1,1},operand_count[2]={0},operator_count[2]={0},uoperator_count[2]={0},control_count[2]={0,0},cl[13]={0},variable_dec[2]={0,0},l,p[2]={0},ct,variable_used[2]={0,0},constant_count[2],s[2]={0},t[2]={0}; char a,b[100],c[100]; char d[100]={0}; j=30; FILE *fp1[2],*fp2; fp1[0]=fopen("program1.txt","r"); fp1[1]=fopen("program2.txt","r"); //the source file is opened in read only mode which will passed through the lexer fp2=fopen("ccv1ouput.txt","wb"); //now lets remove all the white spaces and store the rest of the words in a file if(fp1[0]==NULL) { perror("failed to open program1.txt"); //return EXIT_FAILURE; } if(fp1[1]==NULL) { perror("failed to open program2.txt"); //return EXIT_FAILURE; } i=0; k=0; ct=0; while(ct!=2) { while(!feof(fp1[ct])) { a=fgetc(fp1[ct]); if(a!=' '&&a!='\n') { if (!isalpha(a) && !isdigit(a)) { switch(a) { case '+':{ i=0; cl[0]=1; operator_count[ct]=operator_count[ct]+1;break;} case '-':{ cl[1]=1; operator_count[ct]=operator_count[ct]+1;i=0;break;} case '*':{ cl[2]=1; operator_count[ct]=operator_count[ct]+1;i=0;break;} case '/':{ cl[3]=1; operator_count[ct]=operator_count[ct]+1;i=0;break;} case '=':{a=fgetc(fp1[ct]); if (a=='='){cl[4]=1; operator_count[ct]=operator_count[ct]+1; operand_count[ct]=operand_count[ct]+1;} else { cl[5]=1; operator_count[ct]=operator_count[ct]+1; operand_count[ct]=operand_count[ct]+1; ungetc(1,fp1[ct]); } break;} case '%':{ cl[6]=1; operator_count[ct]=operator_count[ct]+1;i=0;break;} case '<':{ a=fgetc(fp1[ct]); if (a=='=') {cl[7]=1; operator_count[ct]=operator_count[ct]+1;} else { cl[8]=1; operator_count[ct]=operator_count[ct]+1; ungetc(1,fp1[ct]); } break; } case '>':{ ; a=fgetc(fp1[ct]); if (a=='='){cl[9]=1; operator_count[ct]=operator_count[ct]+1;} else { cl[10]=1; operator_count[ct]=operator_count[ct]+1; ungetc(1,fp1[ct]); } break;} case '&':{ cl[11]=1; a=fgetc(fp1[ct]); operator_count[ct]=operator_count[ct]+1; operand_count[ct]=operand_count[ct]+1; variable_used[ct]=variable_used[ct]-1; break; } case '|':{ cl[12]=1; a=fgetc(fp1[ct]); operator_count[ct]=operator_count[ct]+1; operand_count[ct]=operand_count[ct]+1; variable_used[ct]=variable_used[ct]-1; break; } case '#':{ while(a!='\n') { a=fgetc(fp1[ct]); } } } } else { d[i]=a; i=i+1; k=k+1; } } else { //printf("%s \n",d); if((strcmp(d,"if")==0)){ memset ( d, 0, 100 ); i=0; control_count[ct]=control_count[ct]+1; } else if(strcmp(d,"then")==0){ i=0;memset ( d, 0, 100 );control_count[ct]=control_count[ct]+1;} else if(strcmp(d,"else")==0){ i=0;memset ( d, 0, 100 );control_count[ct]=control_count[ct]+1;} else if(strcmp(d,"while")==0){ i=0;memset ( d, 0, 100 );control_count[ct]=control_count[ct]+1;} else if(strcmp(d,"int")==0){ while(a != '\n') { a=fgetc(fp1[ct]); if (isalpha(a) ) variable_dec[ct]=variable_dec[ct]+1; } memset ( d, 0, 100 ); lines_count[ct]=lines_count[ct]+1; } else if(strcmp(d,"char")==0){while(a != '\n') { a=fgetc(fp1[ct]); if (isalpha(a) ) variable_dec[ct]=variable_dec[ct]+1; } memset ( d, 0, 100 ); lines_count[ct]=lines_count[ct]+1; } else if(strcmp(d,"float")==0){while(a != '\n') { a=fgetc(fp1[ct]); if (isalpha(a) ) variable_dec[ct]=variable_dec[ct]+1; } memset ( d, 0, 100 ); lines_count[ct]=lines_count[ct]+1; } else if(strcmp(d,"printf")==0){while(a!='\n') a=fgetc(fp1[ct]); memset(d,0,100); } else if(strcmp(d,"scanf")==0){while(a!='\n') a=fgetc(fp1[ct]); memset(d,0,100);} else if (isdigit(d[i-1])) { memset ( d, 0, 100 ); i=0; constant_count[ct]=constant_count[ct]+1; operand_count[ct]=operand_count[ct]+1; } else if (isalpha(d[i-1]) && strcmp(d,"int")!=0 && strcmp(d,"char")!=0 && strcmp(d,"float")!=0 && (strcmp(d,"if")!=0) && strcmp(d,"then")!=0 && strcmp(d,"else")!=0 && strcmp(d,"while")!=0 && strcmp(d,"printf")!=0 && strcmp(d,"scanf")!=0) { memset ( d, 0, 100 ); i=0; operand_count[ct]=operand_count[ct]+1; } else if(a=='\n') { lines_count[ct]=lines_count[ct]+1; memset ( d, 0, 100 ); } } } fclose(fp1[ct]); operand_count[ct]=operand_count[ct]-5; variable_used[0]=operand_count[0]-constant_count[0]; variable_used[1]=operand_count[1]-constant_count[1]; for(j=0;j<12;j++) uoperator_count[ct]=uoperator_count[ct]+cl[j]; fprintf(fp2,"\n statistics of program %d",ct+1); fprintf(fp2,"\n the no of lines ---> %d",lines_count[ct]); fprintf(fp2,"\n the no of operands --->%d",operand_count[ct]); fprintf(fp2,"\n the no of operator --->%d",operator_count[ct]); fprintf(fp2,"\n the no of control statments --->%d",control_count[ct]); fprintf(fp2,"\n the no of unique operators --->%d",uoperator_count[ct]); fprintf(fp2,"\n the no of variables declared--->%d",variable_dec[ct]); fprintf(fp2,"\n the no of variables used--->%d",variable_used[ct]); fprintf(fp2,"\n ---------------------------------"); fprintf(fp2,"\n \t \t \t"); ct=ct+1; } t[0]=lines_count[0]+control_count[0]+uoperator_count[0]; t[1]=lines_count[1]+control_count[1]+uoperator_count[1]; s[0]=operator_count[0]+operand_count[0]+variable_dec[0]+variable_used[0]; s[1]=operator_count[1]+operand_count[1]+variable_dec[1]+variable_used[1]; fprintf(fp2,"\n the time complexity of program 1 is %d",t[0]); fprintf(fp2,"\n the time complexity of program 2 is %d",t[1]); fprintf(fp2,"\n the space complexity of program 1 is %d",s[0]); fprintf(fp2,"\n the space complexity of program 2 is %d",s[1]); if((t[0]>t[1]) && (s[0] >s[1])) fprintf(fp2,"\n the efficiency of program 2 is greater than program 1"); else if(t[0]<t[1] && s[0] < s[1]) fprintf(fp2,"\n the efficiency of program 1 is greater than program 2 " ); else if (t[0]+s[0] > t[1]+s[1]) fprintf(fp2,"\n the efficiency of program 1 is greater than program 2"); else if (t[0]+s[0] < t[1]+s[1]) fprintf(fp2,"\n the efficiency of program 2 is greater than program 1"); else if (t[0]+s[0] == t[1]+s[1]) fprintf(fp2,"\n the efficiency of program 1 is equal to that of program 2"); fclose(fp2); return 0; } this code basically compares two c codes and finds out the no. of variables declared , used , no. of control statements , no. of lines and no. of unique operators , and operands , so as to find out the time complexity and space complexity of of the two programs given in the text file program1.txt and program2.txt ... Lets say program1.txt is this #include<stdio.h> #include<math.h> int main () { FILE *fp; fp=fopen("output.txt","w"); long double t,y=0,x=0,e=5,f=1,w=1; for (t=0;t<10;t=t+0.01) { //if (isnan(y) || isinf(y)) //break; fprintf(fp,"%ld\t%ld\n",y,x); y = y + ((e*(1 - (x*x))*y) - x + f*cos(w*0.1))*0.1; x = x + y*0.1; } fclose(fp); return (0); } i havent indented it as its just a text file . But my output is totally faulty . Its not able to find the any of the ouput that i need . Where is the bug in this ? I am not able to figure out as the algorithm looks fine .

  Read the article

• std::map default value for build-in type

  - by Qifa Zhao

  Recently, I was confused by the std::map operator[] function. In the MSDN library, it says: "If the argument key value is not found, then it is inserted along with the default value of the data type." I tryed to search much more exactly explanation for this issue. For example here: std::map default value In this page, Michael Anderson said that "the default value is constructed by the default constructor(zero parameter constructor)". Now my quest comes to this:"what the default value for the build-in type?". Was it compiler related? Or is there a standard for this issue by the c++ stardard committee? I did a test on visual studio 2008 for the "int" type, and found the "int" type is construted with the value 0.

  Read the article

• GCC destructor behaviour

  - by joveha

  I've noticed a difference in behaviour for gcc's destructor when compiled under linux and crosscompiled with mingw. On linux the destructor will not get called unless the program terminates normally by itself (returns from main). I guess that kind of makes sense if you take signal handlers into account. On Win32 however, the destructor is called if the program is terminated by say a CTRL-C, but not when killed from the Task Manager. Why is this? And what would you suggest to make the destructor get called no matter how the process terminates - on Win32 in particular? Example code: #include <stdio.h> int main(int argc, char **argv) { printf("main\n"); while(1) {} return 0; } __attribute__((destructor)) static void mydestructor(void) { printf("destructor\n"); }

  Read the article

• Time required for a process to complete

  - by yelkawar

  I am new to C# world. I am attempting to calculate time taken by a algorithum for the purpose of comparison. Following code measures the elapsed time from when a subroutine is called until the subroutine returns to the main program.This example is taken from "Data structures through C#" by Michael McMillan. After running this program the output is Time=0, which is incorrect. The program appears to be logically correct. Can anybody help me. Following is the code using System.Collections.Generic; using System.Collections; using System.Linq; using System.Text; namespace Chap1 { class Program { static void Main(string[] args) { int num1 = 100; int num2 = 200; Console.WriteLine("num1: " + num1); Console.WriteLine("num2: " + num2); Swap<int>(ref num1, ref num2); Console.WriteLine("num1: " + num1); Console.WriteLine("num2: " + num2); string str1 = "Sam"; string str2 = "Tom"; Console.WriteLine("String 1: " + str1); Console.WriteLine("String 2: " + str2); Swap<string>(ref str1, ref str2); Console.WriteLine("String 1: " + str1); Console.WriteLine("String 2: " + str2); Console.ReadKey(); } static void Swap<T>(ref T val1, ref T val2) { T temp; temp = val1; val1 = val2; val2 = temp; } } class Timing { TimeSpan StartTiming; TimeSpan duration; public Timing() { StartTiming = new TimeSpan(0); duration = new TimeSpan(0); } public TimeSpan startTime() { GC.Collect(); GC.WaitForPendingFinalizers(); StartTiming = Process.GetCurrentProcess().Threads[0].UserProcessorTime; return StartTiming; } public void stopTime() { duration = Process.GetCurrentProcess().Threads[0].UserProcessorTime.Subtract(StartTiming); } public TimeSpan result() { return duration; } } }

  Read the article

• jcuda library usage problem

  - by user513164

  hi m very new to java and Linux i have a code which is taken from examples of jcuda.the code is following import jcuda.CUDA; import jcuda.driver.CUdevprop; import jcuda.driver.types.CUdevice; public class EnumDevices { public static void main(String args[]) { //Init CUDA Driver CUDA cuda = new CUDA(true); int count = cuda.getDeviceCount(); System.out.println("Total number of devices: " + count); for (int i = 0; i < count; i++) { CUdevice dev = cuda.getDevice(i); String name = cuda.getDeviceName(dev); System.out.println("Name: " + name); int version[] = cuda.getDeviceComputeCapability(dev); System.out.println("Version: " + String.format("%d.%d", version[0], version[1])); CUdevprop prop = cuda.getDeviceProperties(dev); System.out.println("Clock rate: " + prop.clockRate + " MHz"); System.out.println("Threads per block: " + prop.maxThreadsPerBlock); } } } I'm using Ubuntu as my operating system i compiled it with following command 1:-javac -cp /home/manish.yadav/Desktop/JCuda-All-0.3.2-bin-linux-x86_64 EnumDevices i got following error error: Class names, 'EnumDevices', are only accepted if annotation processing is explicitly requested 1 error i don't know what is the meaning of this error.what should i do to compile the program than i changed the compiling option which is javac -cp /home/manish.yadav/Desktop/JCuda-All-0.3.2-bin-linux-x86_64 EnumDevices.java than i got following error EnumDevices.java:36: clockRate is not public in jcuda.driver.CUdevprop; cannot be accessed from outside package System.out.println("Clock rate: " + prop.clockRate + " MHz"); ^ EnumDevices.java:37: maxThreadsPerBlock is not public in jcuda.driver.CUdevprop; cannot be accessed from outside package System.out.println("Threads per block: " + prop.maxThreadsPerBlock); ^ 2 errors Now I'm completely confused i don't know what to do? how to compile this program ? how to install the jcuda package or how to use it ? how to use package which have only jar files and .so files and the jar files don't having manifest file ? please help me

  Read the article

• Python Beginner: Selective Printing in loops

  - by Jonathan Straus

  Hi there. I'm a very new python user (had only a little prior experience with html/javascript as far as programming goes), and was trying to find some ways to output only intermittent numbers in my loop for a basic bicycle racing simulation (10,000 lines of biker positions would be pretty excessive :P). I tried in this loop several 'reasonable' ways to communicate a condition where a floating point number equals its integer floor (int, floor division) to print out every 100 iterations or so: for i in range (0,10000): i = i + 1 t = t + t_step #t is initialized at 0 while t_step is set at .01 acceleration_rider1 = (power_rider1 / (70 * velocity_rider1)) - (force_drag1 / 70) velocity_rider1 = velocity_rider1 + (acceleration_rider1 * t_step) position_rider1 = position_rider1 + (velocity_rider1 * t_step) force_drag1 = area_rider1 * (velocity_rider1 ** 2) acceleration_rider2 = (power_rider2 / (70 * velocity_rider1)) - (force_drag2 / 70) velocity_rider2 = velocity_rider2 + (acceleration_rider2 * t_step) position_rider2 = position_rider2 + (velocity_rider2 * t_step) force_drag2 = area_rider1 * (velocity_rider2 ** 2) if t == int(t): #TRIED t == t // 1 AND OTHER VARIANTS THAT DON'T WORK HERE:( print t, "biker 1", position_rider1, "m", "\t", "biker 2", position_rider2, "m"

  Read the article

• Data Access Layer in an ASP.NET website

  - by user3519124

  :) i have a DAL class file in my project, that my teacher sent me and explained to me but i did not really understand it. It has number of functions, and I understand only few of them, like with connecting to the database or creating a command object but there are 2 that I dont understand: public static DataTable GetTable(string str) { OleDbConnection con = DAL.GetConnection(); OleDbCommand cmd = DAL.GetCommand(con, str); DataTable dt = new DataTable(); OleDbDataAdapter adp = new OleDbDataAdapter(); adp.SelectCommand = cmd; adp.Fill(dt); return dt; } public static int ExecuteNonQuery(string str) { int num = -1; OleDbConnection con = DAL.GetConnection(); con.Open(); if (con.State == ConnectionState.Open) { OleDbCommand cmd = DAL.GetCommand(con, str); num = cmd.ExecuteNonQuery(); con.Close(); } return num; } thank you :)

  Read the article

• GAE Datastore: persisting referenced objects

  - by David

  Two "I'm sorries" to begin with: 1) I've looked for a solution (here, and elsewhere), and couldn't find the answer. 2) English is not my mother tongue, so I may have some typos and the sort - please ignore them. To the point: I am trying to persist Java objects to the GAE datastore. I am not sure as to how to persist object having ("non-trivial") referenced object. That is, assume I have the following. public class Father { String name; int age; Vector<Child> offsprings; //this is what I call "non-trivial" reference //ctor, getters, setters... } public class Child { String name; int age; Father father; //this is what I call "non-trivial" reference //ctor, getters, setters... } The name field is unique in each type domain, and is considered a Primary-Key. In order to persist the "trivial" (String, int) fields, all I need is to add the correct annotation. So far so good. However, I don't understand how should I persist the home-brewed (Child, Father) types referenced. Should I: Convert each such reference to hold the Primary-Key (a name String, in this example) instead of the "actual" object. So, Vector<Child> offsprings; becomes Vector<String> offspringsNames; ? If that is the case, how do I handle the object at run-time? Do I just query for the Primary-Key from Class.getName, to retrieve the refrenced objects? Convert each such reference to hold the actual Key provided to me by the Datastore upon the proper put() operation? So, Vector<Child> offsprings; becomes Vector<Key> offspringsHashKeys; ? I would very much appreciate all kinds of comments. I have read ALL the offical relevant GAE docs/example. Throughout, they always persist "trivial" references, natively supported by the Datastore (e.g. in the Guestbook example, only Strings, and Longs). Many thanks, David

  Read the article

• How to write a Custom DesignerSerializer for an class used by a Activity (WF)

  - by Stefan Steinegger

  I have a type which is used in a WF activity. It should be serialized. It doesn't work out of the box, most probably because of the private setters in that type. I'm not sure if this is the correct way, but I tried to write my own serializer and declared it on my class. [DesignerSerializer( typeof(FooDesignerSerializer), // my custom serializer typeof(WorkflowMarkupSerializer))] public class Foo { public Foo(int value, string name { // ... } public int Value { get; private set; } public string Name { get; private set; } } Is this the easiest way to get it serialized? How do I write this serializer? That's what I got so far: public class FooDesignerSerializer : WorkflowMarkupSerializer { protected override string SerializeToString( WorkflowMarkupSerializationManager serializationManager, object value) { // how to create a valid / XOML-like string? } }

  Read the article

• Caesar Cipher in Java (Spanish Characters)

  - by Rodolfo

  I've reading this question, and I was wondering if Is there any way to consider the whole range of characters? For example, "á", "é", "ö", "ñ", and not consider " " (the [Space])? (For example, my String is "Hello World", and the standard result is "Khoor#Zruog"; I want to erase that "#", so the result would be "KhoorZruog") I'm sure my answer is in this piece of code: if (c >= 32 && c <= 127) { // Change base to make life easier, and use an // int explicitly to avoid worrying... cast later int x = c - 32; x = (x + shift) % 96; chars[i] = (char) (x + 32); } But I've tried some things, and it didn't work.

  Read the article

• Dynamic object property populator (without reflection)

  - by grenade

  I want to populate an object's properties without using reflection in a manner similar to the DynamicBuilder on CodeProject. The CodeProject example is tailored for populating entities using a DataReader or DataRecord. I use this in several DALs to good effect. Now I want to modify it to use a dictionary or other data agnostic object so that I can use it in non DAL code --places I currently use reflection. I know almost nothing about OpCodes and IL. I just know that it works well and is faster than reflection. I have tried to modify the CodeProject example and because of my ignorance with IL, I have gotten stuck on two lines. One of them deals with dbnulls and I'm pretty sure I can just lose it, but I don't know if the lines preceding and following it are related and which of them will also need to go. The other, I think, is the one that pulled the value out of the datarecord before and now needs to pull it out of the dictionary. I think I can replace the "getValueMethod" with my "property.Value" but I'm not sure. I'm open to alternative/better ways of skinning this cat too. Here's the code so far (the commented out lines are the ones I'm stuck on): using System; using System.Collections.Generic; using System.Reflection; using System.Reflection.Emit; public class Populator<T> { private delegate T Load(Dictionary<string, object> properties); private Load _handler; private Populator() { } public T Build(Dictionary<string, object> properties) { return _handler(properties); } public static Populator<T> CreateBuilder(Dictionary<string, object> properties) { //private static readonly MethodInfo getValueMethod = typeof(IDataRecord).GetMethod("get_Item", new [] { typeof(int) }); //private static readonly MethodInfo isDBNullMethod = typeof(IDataRecord).GetMethod("IsDBNull", new [] { typeof(int) }); Populator<T> dynamicBuilder = new Populator<T>(); DynamicMethod method = new DynamicMethod("Create", typeof(T), new[] { typeof(Dictionary<string, object>) }, typeof(T), true); ILGenerator generator = method.GetILGenerator(); LocalBuilder result = generator.DeclareLocal(typeof(T)); generator.Emit(OpCodes.Newobj, typeof(T).GetConstructor(Type.EmptyTypes)); generator.Emit(OpCodes.Stloc, result); int i = 0; foreach (var property in properties) { PropertyInfo propertyInfo = typeof(T).GetProperty(property.Key, BindingFlags.Public | BindingFlags.Instance | BindingFlags.IgnoreCase | BindingFlags.FlattenHierarchy | BindingFlags.Default); Label endIfLabel = generator.DefineLabel(); if (propertyInfo != null && propertyInfo.GetSetMethod() != null) { generator.Emit(OpCodes.Ldarg_0); generator.Emit(OpCodes.Ldc_I4, i); //generator.Emit(OpCodes.Callvirt, isDBNullMethod); generator.Emit(OpCodes.Brtrue, endIfLabel); generator.Emit(OpCodes.Ldloc, result); generator.Emit(OpCodes.Ldarg_0); generator.Emit(OpCodes.Ldc_I4, i); //generator.Emit(OpCodes.Callvirt, getValueMethod); generator.Emit(OpCodes.Unbox_Any, property.Value.GetType()); generator.Emit(OpCodes.Callvirt, propertyInfo.GetSetMethod()); generator.MarkLabel(endIfLabel); } i++; } generator.Emit(OpCodes.Ldloc, result); generator.Emit(OpCodes.Ret); dynamicBuilder._handler = (Load)method.CreateDelegate(typeof(Load)); return dynamicBuilder; } } EDIT: Using Marc Gravell's PropertyDescriptor implementation (with HyperDescriptor) the code is simplified a hundred-fold. I now have the following test: using System; using System.Collections.Generic; using System.ComponentModel; using Hyper.ComponentModel; namespace Test { class Person { public int Id { get; set; } public string Name { get; set; } } class Program { static void Main() { HyperTypeDescriptionProvider.Add(typeof(Person)); var properties = new Dictionary<string, object> { { "Id", 10 }, { "Name", "Fred Flintstone" } }; Person person = new Person(); DynamicUpdate(person, properties); Console.WriteLine("Id: {0}; Name: {1}", person.Id, person.Name); Console.ReadKey(); } public static void DynamicUpdate<T>(T entity, Dictionary<string, object> properties) { foreach (PropertyDescriptor propertyDescriptor in TypeDescriptor.GetProperties(typeof(T))) if (properties.ContainsKey(propertyDescriptor.Name)) propertyDescriptor.SetValue(entity, properties[propertyDescriptor.Name]); } } } Any comments on performance considerations for both TypeDescriptor.GetProperties() & PropertyDescriptor.SetValue() are welcome...

  Read the article

• Similar route mapping

  - by Denis Agarev

  I need to map to create controller what must response to two urls: "http://localhost/api/controller?id=1" (where only id value can change) "http://localhost/api/controller/anotherId/someconst" (where anotherId is the only one changing part) i map it to such route: routes.MapHttpRoute("Test", "api/{controller}/{id}/{someconst}", new { controller = "Test", someconst = RouteParameter.Optional }); And have to methods in my controller: public void Get(int id) { ... } public void Get(int anotherId, string someconst ) { ... } It works...But it doesn't look nice...cause "string someconst" is not a param, it's just a const part of url. But if i remove "string someconst" param second url wouldn't work. Is it possible to map one controller to two routes to resolve this urls to make it clear without fake param which is a const in fact?

  Read the article

• ASP.NET C# - do you need a separate datasource for each gridview? [closed]

  - by Brian McCarthy

  Do you need a separate datasource for each gridview if each gridview is accessing the same database but different tables in the database? I'm getting an error on AppSettings that says non-invocable member. What is the problem with it? Here's the c# code-behind: protected void Search_Zip_Plan_Age_Button_Click(object sender, EventArgs e) { var _with1 = this.ZipPlan_SqlDataSource; _with1.SelectParameters.Clear(); _with1.ConnectionString = System.Configuration.ConfigurationManager.AppSettings("PriceFinderConnectionString").ToString; _with1.SelectCommand = "ssp_get_zipcode_plan"; _with1.SelectParameters.Add("ZipCode", this.ZipCode.Text); _with1.SelectParameters.Add("PlanCode", this.PlanCode.Text); _with1.SelectParameters.Add("Age", this.Age.Text); _with1.SelectCommandType = SqlDataSourceCommandType.StoredProcedure; _with1.CancelSelectOnNullParameter = false; Search_Results_GridView.DataBind(); } thanks!

  Read the article

• Can/Should you throw exceptions in a c# switch statement?

  - by Kettenbach

  Hi All, I have an insert query that returns an int. Based on that int I may wish to throw an exception. Is this appropriate to do within a switch statement? switch (result) { case D_USER_NOT_FOUND: throw new ClientException(string.Format("D User Name: {0} , was not found.", dTbx.Text)); case C_USER_NOT_FOUND: throw new ClientException(string.Format("C User Name: {0} , was not found.", cTbx.Text)); case D_USER_ALREADY_MAPPED: throw new ClientException(string.Format("D User Name: {0} , is already mapped.", dTbx.Text)); case C_USER_ALREADY_MAPPED: throw new ClientException(string.Format("C User Name: {0} , is already mapped.", cTbx.Text)); default: break; } I normally add break statements to switches but they will not be hit. Is this a bad design? Please share any opinions/suggestions with me. Thanks, ~ck in San Diego

  Read the article

• How does the NSAutoreleasePool autorelease pool work?

  - by jsumners

  As I understand it, anything created with an alloc, new, or copy needs to be manually released. For example: int main(void) { NSString *string; string = [[NSString alloc] init]; /* use the string */ [string release]; } My question, though, is wouldn't this be just as valid?: int main(void) { NSAutoreleasePool *pool; pool = [[NSAutoreleasePool alloc] init]; NSString *string; string = [[[NSString alloc] init] autorelease]; /* use the string */ [pool drain]; }

  Read the article

• Alert dialog is gone before the user see anything

  - by Android Developer

  PopIt("Exit Application", "Are you sure you want to exit?"); public void PopIt( String title, String message ){ new AlertDialog.Builder(this) .setTitle( title ) .setMessage( message ) .setPositiveButton("YES", new OnClickListener() { public void onClick(DialogInterface arg0, int arg1) { //do stuff onclick of YES finish(); } }).setNegativeButton("NO", new OnClickListener() { public void onClick(DialogInterface arg0, int arg1) { //do stuff onclick of CANCEL Toast.makeText(getBaseContext(), "You touched CANCEL", Toast.LENGTH_SHORT).show(); } }).show(); } this alert dialog gone so fast as I cant read or click on it !! why is that ?

  Read the article

• C functions invoked as threads - Linux userland program

  - by Einar

  I'm writing a linux daemon in C which gets values from an ADC by SPI interface (ioctl). The SPI (spidev - userland) seems to be a bit unstable and freezes the daemon at random times. I need to have some better control of the calls to the functions getting the values, and I was thinking of making it as a thread which I could wait for to finish and get the return value and if it times out assume that it froze and kill it without this new thread taking down the daemon itself. Also I could do other things like resetting the ADC before restarting. Is this possible? Pseudo example of what I want to achieve: (function int get_adc_value(int adc_channel, float *value) ) pid = thread( get_adc_value(1,&value); //makes thread wait_until_finish(pid, timeout); //waits until function finishes/timesout if(timeout) kill pid, start over //if thread do not return in given time, kill it (it is frozen) else if return value sane, continue //if successful, handle return variable value and continue Thanks for any input on the matter, examples highly appreciated!

  Read the article

• LINQ DefaultIfEmpty(), generating inferred argument error

  - by Refracted Paladin

  I am trying to get the below linq query to return -1 if there isn't any current value. I was looking at this article on MSDN, here, and it seemed that DefaultIfEmpty() was what I wanted. Unfortunately, I am getting a The type arguments cannot be inferred from the usage. Try specifying the type arguments explicitly. error. I guess I am not sure what that means or what it is telling me to do. Can someone explain, please. public static int CheckForDRIID(int personID) { using (var context = ConnectDataContext.Create()) { var masterIndex = (from applicationAssociation in context.tblApplicationAssociations where applicationAssociation.ApplicationID == 1 && applicationAssociation.PersonID == personID select applicationAssociation.PersonApplicationID).DefaultIfEmpty(-1).Single(); return Convert.ToInt32(masterIndex); } }

  Read the article

• How to get parent item in Treeview

  - by Anu

  Hi,To get the child items as string i used the following code private void treeview1_SelectedItemChanged(object sender, RoutedPropertyChangedEventArgs<object> e) { if (treeview1.SelectedItem != null) { Animal bar = (Animal)treeview1.SelectedItem; string str = bar.Name; int boxty = bar.BoxType; int boxno = bar.BoxNo; } } It works fine .But when i click on parent(instead of + sign),it goes to this code and shows error.Ofcourse im casting SelectedItem to my List-Animal. But i dont want this.I have to check,whether the clciked item is parent,if it is so then i will skip this coding.Only when i click the child items it will go to this coding. How can i do that?How can i identify the selected item is parent.

  Read the article

< Previous Page | 435 436 437 438 439 440 441 442 443 444 445 446  | Next Page >