Is there a way to pass a 2d array to a function in c++ with out having
to specifiy the number of elements in the array. Here is an example
Code:
#include<iostream>
using namespace std;
int main()
{
int array[10][10];
fill(array,rows,cols);
return 0;
}
void fill(int array[10][10], rows,cols)
{
int i, j;
for(i=0;i<10;i++)
for(j=0;j<10;j++)
array[i][j]=0;
}
array needs to have the [10][10] or at least
[][10]. is there a way i can make it so it
only needs [][]?
You could consider
a) packaging your matrix into a class.
b) turning that class into a template.
a) has the advantage that it separates the implementation from the
interface.
b) makes the whole thing more generic.
E.g.:
template < typename arithmetic_type, unsigned long ROWS, unsigned long COLSclass matrix {
public:
typedef arithmetic_type value_type;
static
const unsigned long rows = ROWS;
static
const unsigned long cols = COLS;
private:
value_type data [ rows ][cols];
public:
value_type & operator() ( unsigned long row_index,
unsigned long col_index ) {
return( data[row_index][col_index] );
}
value_type const & operator() ( unsigned long row_index,
unsigned long col_index ) const {
return( data[row_index][col_index] );
}
};// matrix
template < typename arithmetic_type, unsigned long ROWS, unsigned long COLSvoid fill_matrix ( matrix< arithmetic_type, ROWS, COLS > & matr ) {
for ( unsigned long r = 0; r < ROWS; ++r ) {
for ( unsigned long c = 0; c < COLS; ++c ) {
matr(r,c) = 0;
}
}
}
typedef matrix< float, 3001, 204 > MediumMatrix;
int main ( void ) {
MediumMatrix mat;
fill_matrix( mat );
}
Note in particular, how template resolution allows you to not explicitly
pass the dimensions of mat to the function fill_matrix(). The static type
of the object mat is all that the compiler needs to choose the right
dimensions.
Best
Kai-Uwe Bux
i know