Solved

Pointer

Posted on 2002-05-29
4
162 Views
Last Modified: 2010-04-02
Can anyone made a code that creates array of chars mychars(first char has value '3' ,2 char:'.',3:'1',4:'4')and then converts it into float mynumber.
Tnx.
0
Comment
Question by:rv_man
  • 2
4 Comments
 
LVL 30

Expert Comment

by:Axter
ID: 7042607
rv_man,
Is this homework?

It's agaisnt EE policy to do homework for questioners.
0
 
LVL 30

Expert Comment

by:Axter
ID: 7042610
Please provide some of your code, and we can assist you with specific questions.
0
 
LVL 86

Accepted Solution

by:
jkr earned 100 total points
ID: 7042650
Use 'strtod()' or 'atof()':

/* STRTOD.C: This program uses strtod to convert a
 * string to a double-precision value; strtol to
 * convert a string to long integer values; and strtoul
 * to convert a string to unsigned long-integer values.
 */

#include <stdlib.h>
#include <stdio.h>

void main( void )
{
   char   *string, *stopstring;
   double x;
   long   l;
   int    base;
   unsigned long ul;
   string = "3.1415926This stopped it";
   x = strtod( string, &stopstring );
   printf( "string = %s\n", string );
   printf("   strtod = %f\n", x );
   printf("   Stopped scan at: %s\n\n", stopstring );
   string = "-10110134932This stopped it";
   l = strtol( string, &stopstring, 10 );
   printf( "string = %s", string );
   printf("   strtol = %ld", l );
   printf("   Stopped scan at: %s", stopstring );
   string = "10110134932";
   printf( "string = %s\n", string );
   /* Convert string using base 2, 4, and 8: */
   for( base = 2; base <= 8; base *= 2 )
   {
      /* Convert the string: */
      ul = strtoul( string, &stopstring, base );
      printf( "   strtol = %ld (base %d)\n", ul, base );
      printf( "   Stopped scan at: %s\n", stopstring );
   }
}

/* ATOF.C: This program shows how numbers stored
 * as strings can be converted to numeric values
 * using the atof, atoi, and atol functions.
 */

#include <stdlib.h>
#include <stdio.h>

void main( void )
{
   char *s; double x; int i; long l;

   s = "  -2309.12E-15";    /* Test of atof */
   x = atof( s );
   printf( "atof test: ASCII string: %s\tfloat:  %e\n", s, x );

   s = "7.8912654773d210";  /* Test of atof */
   x = atof( s );
   printf( "atof test: ASCII string: %s\tfloat:  %e\n", s, x );

   s = "  -9885 pigs";      /* Test of atoi */
   i = atoi( s );
   printf( "atoi test: ASCII string: %s\t\tinteger: %d\n", s, i );

   s = "98854 dollars";     /* Test of atol */
   l = atol( s );
   printf( "atol test: ASCII string: %s\t\tlong: %ld\n", s, l );
}


Axter, having seen the other Qs posted by rv_man, I don't think it's homework...
0
 

Author Comment

by:rv_man
ID: 7042734
First of all thats not my homework. I just "playing" with
direct3d and to "play" with it I must know how pointer and stl works. I "prof." in java but I just began learning c++. I know what pointer is but I don't know how to work with it :)
Now my question:
I have
int iInTextLen = 20;
char *in_text = new char[iInTextLen];
float iMyNumber;


I have in WM_CHAR messege:
in_text[strlen(in_text)]=(char)wParam;
So, every time when I pressing... ok.

I running my programm and typing for example "new vector 60.0f 60.0f 0.5f 1.0f 0xffff0000"
So, it goes to in_text.
Now I want ,for example, place 60.0f from in_text in iMyNumber.

Thats it. I asking it because I don't even know how to do it: with pointer or with help of stl.

Sorry for my English :)

Waiting for answer.
0

Featured Post

Networking for the Cloud Era

Join Microsoft and Riverbed for a discussion and demonstration of enhancements to SteelConnect:
-One-click orchestration and cloud connectivity in Azure environments
-Tight integration of SD-WAN and WAN optimization capabilities
-Scalability and resiliency equal to a data center

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Article by: SunnyDark
This article's goal is to present you with an easy to use XML wrapper for C++ and also present some interesting techniques that you might use with MS C++. The reason I built this class is to ease the pain of using XML files with C++, since there is…
IntroductionThis article is the second in a three part article series on the Visual Studio 2008 Debugger.  It provides tips in setting and using breakpoints. If not familiar with this debugger, you can find a basic introduction in the EE article loc…
The viewer will learn how to clear a vector as well as how to detect empty vectors in C++.
The viewer will be introduced to the member functions push_back and pop_back of the vector class. The video will teach the difference between the two as well as how to use each one along with its functionality.

809 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question