How to make List from Numpy Matrix in Python

Question

I using the dot() function from numpy to multiply a matrix of 3x3 with a numpy.array of 1x3. The output is for example this:

[[ 0.16666667 0.66666667 0.16666667]]

which is of type:

<class 'numpy.matrixlib.defmatrix.matrix'> 

how can I convert this to a list. Because I know the result will always be a matrix of 1x3 so it should be coverted to a list because I need to be able to loop through it later for calculation the pearson distance of two of those lists.

So to summarize: how can I make a list from this matrix?

Answer 1

May not be the optimal way to do this but the following works:

a = numpy.matrix([[ 0.16666667, 0.66666667, 0.16666667]]) list(numpy.array(a).reshape(-1,)) 

or

numpy.array(a).reshape(-1,).tolist() 

or

numpy.array(a)[0].tolist() 

Answer 2

Use the tolist() method on the matrix object :

>>> import numpy >>> m = numpy.matrix([1, 2, 3]) >>> type(m) <class 'numpy.core.defmatrix.matrix'> >>> m.tolist() [[1, 2, 3]]