How to read in multiple floats on one line and then add them to an array?

Question

I am trying to read in a line of floating point values like

1.1 -100.0 2.3

and I need to store these in an array. I am using the fgets() method to convert the input into a string. Is there anyway I can use this string to populate a float array with the values? Or is there a better way to do this?

#include <stdio.h>

int main(){
    char input [500];
    float values [50];
    fgets(input, 500, stdin);
// now input has a string with all the values
// and the values array needs to be filled with the values
}

Answer 1

You can apply sscanf for the inputted string.

Here is a simplified demonstration program.

#include <stdio.h>

int main(void) 
{
    char input[20];
    float values[3];
    
    fgets( input, sizeof( input ), stdin );
    
    size_t n = 0;
    char *p = input;
    
    for ( int pos = 0; n < 3 && sscanf( p, "%f%n", values + n, &pos ) == 1; p += pos )
    {
        ++n;
    }
    
    for ( size_t i = 0; i < n; i++ )
    {
        printf( "%.1f ", values[i] );
    }
    
    putchar( '\n' );
    
    return 0;
}

If the inputted string is

1.1 -100.0 2.3

then the output of the array values is

1.1 -100.0 2.3