Scientific Computing with Python 3

Functions to construct arrays

The usual way to set up an array is via a list. But there are also a couple of convenient methods for generating special arrays, which are given in the following table (Table 4.5):

Methods	Shape	Generates
zeros((n,m))	(n,m)	Matrix filled with zeros
ones((n,m))	(n,m)	Matrix filled with ones
diag(v,k)	(n,n)	(Sub-, super-) diagonal matrix from a vector v
random.rand(n,m)	(n,m)	Matrix filled with uniformly distributed random numbers in (0,1)
arange(n)	(n,)	First n integers
linspace(a,b,n)	(n,)	Vector with n equispaced points between a and b

Table 4.5: Commands to create arrays

These commands may take additional arguments. In particular, the commands zeros, ones, and  ...