#include "range.h"

//--------------- range functions -------------------
matrix range(int start, int stride, int stop) {
    if (stride < 1)
	throw invalid_argument("stride must be positive.");
    int size;
    if (stop >= start)
	size = (stop - start + stride - 1) / stride;
    else 
	size = 0;
    matrix result(1, size);
    for (int k=0; k < size; k++)
	result(0, k) = start + k*stride;
    return result;
}

matrix range(int start, int stop) {
    return range(start, 1, stop);
}

matrix range(int start) {
    return matrix(1,1,start);
}