problem with reading floatting numbers

Hi
i want to read float number from file .txt without using vectors , umbers are seprated by space , the nfor that i make like that

Code:

---

if (fp != NULL)

    {

        while (fgets(line, 1000, fp))

        {
            while(line[counter+1]!=NULL)
            {
if (line[counter]==' ')
                {
number=number/(Ogre::Math::Pow(10,number_float));
                        printf ("le nombre= %f",number);
}
else
                {
                   
                if (line[counter]=='.')
                {

                    number_float=0;
                    fl=true;
                   
                }
                else
                {
                if(fl==false)
                {
                    number=number*10+((int)line[counter]-(int)'0');
                   
                }
                else
                {
                    number_float++;
                    number=number*10+((int)line[counter]-(int)'0');
                }
                }
                }
counter++;

---

that's seem work
but now i have problem with signe '+' , '-' i do not know how i make to read the positif and negatif numbers
have you an idea ?

strtod(3) - Linux man page
Using endptr, you can step through a whole string of space-separated numbers, and extract each one in turn.

hi i did not understand how it work
in my file.txt the data are like that
0.10 -12.154 +0.002

Like so

Code:

---

$ cat bar.c
#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
int main ()
{
    char line[] = "0.10 -12.154 +0.002 1e1000\n";  // like fgets gives you
    char *p = line, *endp;
    while ( *p != '\0' ) {
        double d = strtod(p,&endp);
        if ( p == endp ) break;
        if ( errno == 0 ) {
            printf("Found value=%f\n", d );
            p = endp;
        } else {
            perror("Failed");
            break;
        }
    }
    return 0;
}
$ ./a.out
Found value=0.100000
Found value=-12.154000
Found value=0.002000
Failed: Numerical result out of range

---

thanks for the code , but what represent " errno" , you did not initialize it

"errno" is a macro (defined in <errno.h>) used by many standard functions to store an error code in case of errors.

Bye, Andreas

BUT if i do not delete " if ( errno == 0 ) {" i will enter in infinite loop

It's necessary code.

What is your problem with checking a function for errors, by examining the errno variable declared in errno.h?

Hi sorry i just see the reply .

id not know where is exactelly the problem ,
when i add if ( errno == 0) it do not execute " printf("Found value=%f\n", d );
p = endp;"
but it pront to me : failed:no such file or directory
i see the value of errno and i found it : 0.00000 so why it do not enter ?

i have another question , i have this struct

Code:

---

struct  joint_angle
    {
        int  count;

        Ogre::Vector3  orient;
    }J;
    struct pose
    {
        float time;
      std::vector<joint_angle> angle;
    }P;

---

where time is the first number(float) in the line
so , i must store each line in "pose"
but it does not work for me

Are you aware that this is C++ and not C? :)
In addition let me inform you that we are in the C thread. The forum has a C++ thread.

hi,
yes i know that i am in c forum ,
but because i hvae some lines in c, and the others are in c++ i am not sure where i put my question

No this is not my point. This is the best forum I know for C++ and C. Might be for C#, but I am not familiar with this language, so I can't judge.

If you see in the main page of the forum, there are three threads, one for C++, one for C and one for C#.

By posting in the right one, you have more chances of someone familiar with C++ to help you.

Also I would suggest not to go and post to the C++ thread now. This is something to remember for the next time you post.
If you do not find the post here, this means that it has been moved to the C++ thread.

thanks for the suggestion

i see that's no reply , for that i will transfer it to the c++ forum