numcpp

A C++ library with a numpy like interface for handling large, multi-dimensional arrays and matrices

This project is a learning exercise for the author. It is not intended as a production library for other users.

Current API

Template Aliasing

The numcpp library is designed to be used with a type alias to make the syntax simpler without reducing flexibility.

using nc = numcpp::numcpp<>;

The default numcpp template type is double. Thus, the above is equivalent to:

using nc = numcpp::numcpp<double>;

Other available types include:

Floating Point	Integers	Unsigned Integers
float	char	unsigned char
double	short	unsigned short
long double	int	unsigned int
	long	unsigned long
	long long	unsigned long long

Array Creation

Method	Description
nc::empty(int n)	Create an uninitialised one dimensional array of length n
nc::empty({i, j, ...})	Create an uninitialised multi dimensional array of shape {i, j, ...}
nc::zeros(int n)	Create a one dimensional array of length n initialised to 0
nc::zeros({i, j, ...})	Create a multi dimensional array of shape {i, j, ...} initialised to 0
nc::ones(int n)	Create a one dimensional array of length n initialised to 1
nc::ones({i, j, ...})	Create a multi dimensional array of shape {i, j, ...} initialised to 1
nc::full(int n, double v)	Create a one dimensional array of length n initialised to v
nc::full({i, j, ...}, double v)	Create a multi dimensional array of shape {i, j, ...} initialised to v
nc::eye(int N, int M = 0, int k = 0)	Create a two dimensional array with ones on the diagonal and zeros elsewhere (M is number of columns and k is the index of the diagonal)
nc::identity(int n)	Create a two dimensional (square) array with ones on the main diagonal and zeros elsewhere

Array Operations

Method	Description
ndarray::transpose()	Transpose an array

Examples

#include <iostream>
#include <numcpp/numcpp.h>

using nc = numcpp::numcpp<double>;

int main()
{
    auto m{ nc::identity(5) };

    std::cout << m.as_string() << '\n';

    /* Prints:
    [
      [1.00000, 0.00000, 0.00000, 0.00000, 0.00000], 
      [0.00000, 1.00000, 0.00000, 0.00000, 0.00000], 
      [0.00000, 0.00000, 1.00000, 0.00000, 0.00000], 
      [0.00000, 0.00000, 0.00000, 1.00000, 0.00000], 
      [0.00000, 0.00000, 0.00000, 0.00000, 1.00000], 
    ] */

    return 0;
}