错误:对数学函数的未定义引用

Question

这是函数指针程序:demo.c

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

void tabulate(double (*f)(double), double first, double last, double incr);

int main(void) {

    double final, increment, initial;

    printf("Enter initial value: ");
    scanf("%lf", &initial);

    printf("Enter final value: ");
    scanf("%lf", &final);

    printf("Enter increment: ");
    scanf("%lf", &increment);

    printf("\n      x       cos(x)"
           "\n   -------    -------\n");
    tabulate(cos, initial, final, increment);
    return 0;
}

void tabulate(double (*f)(double), double first, double last, double incr) {
    double x;
    int i, num_intervals;

    num_intervals = ceil((last - first)/incr);
    for(i=0; i<=num_intervals; i++) {
        x = first + i * incr;
        printf("%10.5f %10.5f\n", x, (*f)(x));
    }
}

当我尝试运行此代码时,收到此消息:

/tmp/ccQ4IZeD.o: In function `main':
demo.c:(.text+0x92): undefined reference to `cos'
/tmp/ccQ4IZeD.o: In function `tabulate':
demo.c:(.text+0xe3): undefined reference to `ceil'
collect2: error: ld returned 1 exit status

这意味着什么,因为cos和ceil是<math.h>文件功能.这是因为OS(ubuntu 13.10 32位),因为这个程序是在其他系统上工作的.

如果是,那么在我的系统上运行什么解决方案.

Answer 1

你必须-lm在链接时使用.