Basic Math Problem. Undefined Math Functions

Code:

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#include <stdio.h>
#include <math.h>

int main(void)
{

        double x;
       
        printf("Enter a number: ");
        scanf("%lf",&x);
       
        printf("\n\nOriginal value: %lf",x);
        printf("\nCeil: %lf",ceil(x));
        printf("\nFloor: %lf",floor(x));
       
        if (x >= 0)
                printf("\nSquare root: %lf",sqrt(x));
        else
                printf("\nNegative Number");
               
        printf("\nCosine: %lf\n",cos(x));
        return 0;

}

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A very simple example into using some of the Math functions found in math.h unfortunately gcc is complaining about the functions being undefined

Quote:

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/tmp/ccRRA7p2.o(.text+0x57): In function `main':
: undefined reference to `ceil'
/tmp/ccRRA7p2.o(.text+0x83): In function `main':
: undefined reference to `floor'
/tmp/ccRRA7p2.o(.text+0xc1): In function `main':
: undefined reference to `sqrt'
/tmp/ccRRA7p2.o(.text+0xfb): In function `main':
: undefined reference to `cos'
collect2: ld returned 1 exit status

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The compile command if this helps

Quote:

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gcc math.c -o math -W -Wall -ansi

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Bit puzzled to why I am getting the errors since ive included the header file.

Try this:

Code:

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gcc math.c -o math -W -Wall -ansi -lm

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You just need to link in the math library