Why does malloc() not allocate correct size of memory when using a pointer to `double`? [duplicate]

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• How to find the 'sizeof'(a pointer pointing to an array)? 11 answers

Here is the essence of what I am trying to do:

double *E; //Array of doubles
int N;  //The eventual size of the array, typically >1

// some code where variable N gets assigned

//inside of some function
E = malloc(sizeof(double)*N);

printf("size of E = %lun",sizeof(E)/sizeof(E[0])); //checking size of array E

The output of this code is "size of E = 1", regardless of the actual value of N. Why does the malloc() function not allocate the correct size in memory?

I know this seems very rudimentary, but I cannot understand why this would not work.

Any insight would be greatly appreciated.