[c] Float To String

[mackol]

does one exist?

i know there is strtol and stuff like that

but is there one that goes the other way

thanks

[Gumboot]

How about sprintf()?

Something like:

#include <stdio.h>
...
char dest[20];
float num = 3.141592653879;
sprintf(dest, "%f", num);

[mackol]

uggh why didnt i think of that

i was constantly stuck with the idea of using sscanf but that wasnt working so finally i created a custom function to check whether a input consists of at least 2 decimal integers

let me post it

float checkAid (char *aidStr)
{
	float aid;
	char *endPtr;
	int x, y;

	x = strlen (aidStr);
	y = (strcspn (aidStr, ".")) + 1;

	if ((x - y) != 2)
	{
  printf("Please re-input the amount with exactly 2 decimal digits\n");
  return 0;
	}

	aid = (float)(strtod(aidStr, &endPtr));
	return aid;
}

with aidStr being a string containg the input from the user.. :)

thanks mate

[mackol]

hey i found a fucntion, which is not ANSI C but which is for that purpose

it is

gcvt and gcvtf

here is a link for the info

http://www.redhat.com/docs/manuals/gnupro/...le_or_floa.html

for those who are lazy to click on the link

gvcvt, gcvtf

[format double or float as string]--------------------------------------------------------------------------------

SYNOPSIS

#include <stdlib.h>

char *gcvt(double val, int precision, char *buf);

char *gcvtf(float val, int precision, char *buf);

DESCRIPTION

gcvt writes a fully formatted number as a null-terminated string in the buffer, *buf. gcvtf produces corresponding character representations of float numbers.

gcvt uses the same rules as the printf format, %.precisiong?only negative values are signed (with -), and either exponential or ordinary decimal-fraction format is chosen, depending on the number of significant digits (specified by precision).

RETURNS

The result is a pointer to the formatted representation of val (the same as the argument, buf).

COMPLIANCE

Neither function is ANSI C.

Supporting OS subroutines required: close, fstat, isatty, lseek, read, sbrk, write.