Pass function pointer to another function - C Pointer

C examples for Pointer:Function Pointer

  1. HOME
  2. C
  3. Pointer
  4. Function Pointer

Description

Pass function pointer to another function

Demo Code

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

#define ARRLENGTH 20//from ww w  .  j ava  2s . co m

void transform(const double * source, double * target, int n, double (*func)(double));
double squared(double);
double cubed(double);

int main(void){
  double source[ARRLENGTH];
  double target[ARRLENGTH];

  for (int i = 0; i < ARRLENGTH; i++)
    source[i] = i;

  transform(source, target, ARRLENGTH, sin);
  for (int i = 0; i < ARRLENGTH; i++)
  {
    printf("sin(%.2f) = %.2f\n", source[i], target[i]);
  }
  puts("\n");

  transform(source, target, ARRLENGTH, tan);
  for (int i = 0; i < ARRLENGTH; i++)
  {
    printf("tan(%.2f) = %.2f\n", source[i], target[i]);
  }
  puts("\n");

  transform(source, target, ARRLENGTH, squared);
  for (int i = 0; i < ARRLENGTH; i++)
  {
    printf("%.2f ^ 2 = %.2f\n", source[i], target[i]);
  }
  puts("\n");

  transform(source, target, ARRLENGTH, cubed);
  for (int i = 0; i < ARRLENGTH; i++)
  {
    printf("%.2f ^ 3 = %.2f\n", source[i], target[i]);
  }
  puts("\n");

  return 0;
}

void transform(const double * source, double * target, int n, double (*func)(double))
{
  for (int i = 0; i < n; i++)
    target[i] = func(source[i]);

  return;
}

double squared(double x)
{
  return x * x;
}

double cubed(double x)
{
  return x * x * x;
}

Result


Related Tutorials