The apmatrix class

The apmatrix class implements resizable two-dimensional arrays with safe subscripting. It is similar to the apvector class with the following differences --

Here are examples of the four apmatrix constructors -
  1. apmatrix words;
    // empty (zero-size) 2-D array of apstrings
  2. apmatrix table(10,2);
    // matrix of doubles with 10 rows and 2 columns
  3. apmatrix board(8,8,'X');
    // 8 by 8 matrix of chars filled with 'X'
  4. apmatrix newboard ( board);
    // second 8 by 8 matrix copied from board x.

Here are some more examples of how to use apmatrices in a program -

#include "apmatrix.h"		// include the header file 
int rows = table.numrows( );	// determine the current number of rows of the matrix
int cols = table.numcols( );	// determine the current number of columns of the matrix
table.resize(5,3);		// set new dimensions of the matrix, truncating extra 
				// elements and filling new elements with default values,
				// (zeros for int, double, char types)
table[0][1] = 4.2;		// store 4.2 in the first row, second column of the matrix
				// at runtime checks that subscripts are within legal range
These two prototype functions show how to always pass matrix objects by reference.
void fillMatrix(apmatrix &table);
	// Note that the & must be explicitly used when a matrix object is passed by reference.

void displayMatrix(const apmatrix &table);
	// To avoid unnecessary copying, do not pass an object by value .
	// Pass by reference using the keyword const to ensure the object cannot be changed

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