Question

when I try to compile my code below I get the following errors:

error C2440: ‘>=’ : cannot convert from ‘double *’ to ‘double’

error C2440: ‘>=’ : cannot convert from ‘double *’ to ‘double’

I believe I’m dereferencing everything correctly

#define TRUE 1
#define FALSE 0;

#include <stdio.h>

typedef struct Con{
  double samTime[2];
  double sen[2];
  int test[2];
} CON, *CON_PTR;

void GM(double **TTXY) {
  int NoS;
  int numOfSen = 2;
  int startTime =0;
  CON con;

  if((con = (CON_PTR) malloc(numOfSen*sizeof(CON)))==NULL) {
    printf(“Malloc failed\n”);
    exit(1);
  }
  for (NoS=0;NoS<numOfSen;NoS++) {
    con[NoS].samTime[0] = startTime;
    con[NoS].samTime[1] = startTime;
    con[NoS].sensor[0] = 0;
    con[NoS].sensor[1] = 0;
    con[NoS].test[0] = FALSE;
    con[NoS].test[1] = FALSE;
  }

  if (con[NoS].samTime[0] >= TTXY[1]) {
    con[NoS].test[0] = TRUE;
  }
  if (con[NoS].samTime[1] == TTXY[1]) {
    con[NoS].test[1] = TRUE; 
  }
}

Answer 1

First, there’s a missing semicolon

int NoS

and your main function is not correct, this must be one of

int main()
int main(int argc, char **argv)
void main() // not standard but allowed by some compilers (with warning)

and as to your question, no you’re not dereferencing it right, as your TTXY array is 2-dimensional. So it should be something like

if (con[NoS].samTime[0] >= TTXY[1][some other number]) {

whatever works for your code. And you should use more descriptive names for your variables if others are supposed to understand the code.

If TTXY should really be a one-dimensional array, then you don’t need to pass it by reference (function(&TTXY)), passing the pointer value (function(TTXY)) will be enough and more readable.