Any Smart guy can figure this out? Should be simple problem.

I am getting this error when want to compile.

Code:

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/tmp/ccmvPe9e.o: In function `stdData':
problem.c:(.text+0x56b): undefined reference to `sqrt'
collect2: ld returned 1 exit status

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And this is the "StdDate" below. Where is the problem? sqrt???

Code:

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double stdData (double x[], int n)/* function to find the standard deviation */


{
        int i;


        double sum = 0, sum1 = 0;


        double sum2, std;


        for (i=0; i<n; i++){


                sum1 = sum1 + (x[i]*x[i]);


                sum = sum + x[i];


        }


        sum2 = (sum * sum)/(n*n);


        std = sqrt(sum1- sum2);


        return (std);


}

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Have you included math.h?

Quote:

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Originally Posted by Adak

Have you included math.h?

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Yes. I did do the math.h Could you look at my code and see if you can fix it??

Code:

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  Descrition: Implement a menu managing array data such that the program asks multiple questions to the user and executes the operation using the method he chooses.
*/


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


/*function definitions*/
double sumData (double x[], int n);//returns the sum of the given set.
double medianData (double x[], int n);//returns the median of the given set.
double stdData (double x[], int n);// returns the standad derivation of the given set.
double rangeData (double x[], int n);//returns the range of the given set.
void freqData (double x[], int n);//displays the frequency distribution in the given ranges.
double meanData(double x[], int n);//returns the mean of the data set.
void setData(double x[], int n);// returns the array as a whole.
void bubble_sort(double x[], int n);//to search the array.

int main()
{
        int size=100;
        double array[size];
        int i, x, c;


        printf ("Please enter the size of you array:");
        scanf ("%d", &size);


        for (i=0; i<size; i++) {
                printf("Enter element %d of the array:", i);
                scanf("%lf", &array[i]);
        }


        printf("Please select a number among the following operations:\n");
        printf("1.Display the data set\n2.Calculate the mean and");
        printf("sum of the data set\n3.Calculate the median of the data set\n");
        printf("4.Calculate the standard deviation of the data set\n5.");
        printf("Find range of the data set\n6.Display a frequency distribution\n");
        printf("7.Quit\n");
        scanf("%d", &c);
    while (c<1 || c>7) {
                printf("\aYou have entered an ivalid number; try again.\n");
                printf("Please select a number among the following operations:\n");
                printf("1.Display the data set\n2.Calculate the mean and");
                printf("sum of the data set\n3.Calculate the median of the data set\n");
                printf("4.Calculate the standard deviation of the data set\n5.");
                printf("Find range of the data set\n6.Display a frequency distribution\n");
                printf("7.Quit\n");
                scanf("%d", &c);
        }
        if (c==1) {
                setData (array, size); //call the function to display the array.
        }
        else if (c==2){// displays both the mean and sum.
                meanData(array, size);
                sumData(array, size);
                printf("mean of the data set:%f\n the sum is:%f\n", meanData(array, size), sumData(array, size));
        }
 else if (c==3){//displays median
                medianData(array, size);
                printf("median of the data set: %f\n", medianData(array, size));


        }
        else if (c==4){
                stdData(array, size); //to display the deviation.
        printf("The standard deviation of the data set:%f\n", stdData(array, size));
        }
        else if (c==5){// Printing the range on the screen.
                rangeData(array, size);
                printf("The range of this data set is:%f\n", rangeData(array, size));
        }
        else if (c==6){//returning the frequency in interval ranges.
                freqData(array, size);
        }
        else if (c==7){//Quit the program.
                printf("The program ends here.\n");
        }
        return 0;
}
/*function definitions*/


void setData (double x[], int n)/* function to display the array pr set data*/


{


        int i;


        for (i=0; i<n; i++){
                printf("%f ", x[i]);
        }
}


double meanData( double x[], int n)/* function to calculate the mean*/


{


        int i;


        double sum =0;
        for (i=0; i<n; i++){
                sum = sum + x[i];
        }
        return (sum/n);


}


double sumData( double x[], int n)/*function to calculate the sum*/


{


        int i;


        double sum = 0;


        for (i=0 ;i<n; i++){
                sum = sum + x[i];
        }


        return (sum);


}


void bubble_sort( double x[], int n)/* function to sort data in increasing order */


{


        int i,j;


        double temp;


        for (i=0; i<n-1; i++){
                for (j=i+1; j<n; j++){


                        if ( x[i] > x[j]){


                                temp = x[i];


                                x[i] = x[j];


                                x[j] = temp;


                        }


                }


        }
}


double medianData (double x[], int n) /*function to calculate the median of the data set */


{


        double Middle;
        int h1, h2;


        bubble_sort(x,n);


        if (n%2 == 0){/*if n is even */


                h1 = n/2;
                h2 = (n/2) - 1;


                Middle = ((x[h1] + x[h2])/2);


        }


        else { //if n is odd
                Middle = x[n/2];


        }


        return ( Middle );


}


double stdData (double x[], int n)/* function to find the standard deviation */


{


        int i;


        double sum = 0, sum1 = 0;


        double sum2, std;


        for (i=0; i<n; i++){


                sum1 = sum1 + (x[i]*x[i]);


                sum = sum + x[i];
               



        }


        sum2 = (sum * sum)/(n*n);


        std = sqrt((sum1/n) - sum2);


        return (std);


}


double rangeData(double x[], int n)/* calculting the range of the data set */


{


        int i;


        double max, min, range;


        max = x[0];


        min = x[0];
 for (i = 0; i<n; i++){


                if( x[i] < min){//searching for the minimum element


                        min = x[i];


                }


                if (x[i] > max){//searching for the maximum element


                        max = x[i];


                }


        }


        range = max - min;//calculating the range
        return (range);


}


void freqData (double x[], int n)/*displaying the frequency */
{


        int i;
        int freq1 = 0;
        int freq2 = 0;
        int freq3 = 0;
        int freq4 = 0;


        bubble_sort(x,n);/*sorting the array values */


        for (i=0; i<n; i++){
                if (x[i] < 0){
                        freq1 = freq1 + 1;


                }


                else if (x[i]>= 0 && x[i]<10){


                        freq2 = freq2 + 1;


                }
                else if (x[i]>= 10 && x[i]<100){


                        freq3 = freq3 + 1;


                }


                else {


                        freq4 = freq4 +1;


                }


        }//displaying ranges.


        printf ("%s%13s\n", "Interval", "Frequency" );
        printf ("(-inf , 0)%13d\n", freq1);
        printf ("[0, 10)%10d\n", freq2);
        printf ("[10, 100)%9d\n", freq3);
        printf ("[100,+inf )%11d\n", freq4);
}

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You need to add "-lm" to your compiler command line.

Quote:

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Originally Posted by brewbuck

You need to add "-lm" to your compiler command line.

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I did and I am getting this
gcc: lm: No such file or directory

http://cboard.cprogramming.com/c-pro...look-mine.html -- same guy, same question, same answer

Quote:

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Originally Posted by smokeyangel

http://cboard.cprogramming.com/c-pro...look-mine.html -- same guy, same question, same answer

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Hey guys I got it!!!!! Thank you so much for your times! I am including a link below for everyone for lunch. FREE IHOP lunch.

[QUOTE=kevave;1070123]Hey guys I got it!!!!! Thank you so much for your times! I am including a link below for everyone for lunch. FREE IHOP lunch.


Ugh, marketing spam? srsly?