Question

I have seperate functions for reading from a text file (depending on whether its an int, float or double). I would like just one function with an additional argument (without using a subsequent IF statement). Does anyone have ideas?

Below is the form of my current functions.

float * read_column_f (char * file, int size_of_col){
...
col = (float*) malloc (height_row * sizeof(float));
...  return(col);}


double *    read_column_d (char * file, int size_of_col){
...
col = (double*) malloc (height_row * sizeof(double));
...  return(col);}


int *   read_column_i (char * file, int size_of_col){
...
col = (int*) malloc (height_row * sizeof(int));
...  return(col);}

EDIT: I want to implement this in C++, the C-style syntax used is due to memory preference.

Answer 1

You can’t overload on return types. You either return value by reference as a function parameter:

void read_column (char * file, int size_of_col, float&);
void read_column (char * file, int size_of_col, int&);

…

or create a template:

template<class T> T read_column (char * file, int size_of_col);