dimensional « numpy « Python Data Type Q&A

1. Indexing one-dimensional numpy.array as matrix    stackoverflow.com

I am trying to index a numpy.array with varying dimensions during runtime. To retrieve e.g. the first row of a n*m array a, you can simply do

a[0,:]

2. How can I get the product of all elements in a one dimensional numpy array    stackoverflow.com

I have a one dimensional NumPy array:

a = numpy.array([2,3,3])

3. Iteration through all 1 dimensional subarrays of a multi-dimensional array    stackoverflow.com

What is the fastest way to iterate through all one dimensional sub-arrays of an n dimensional array in python. For example consider the 3-D array:

import numpy as np 
a = np.arange(24)
a = ...

4. In numpy, what is the fastest way to multiply the second dimension of a 3 dimensional array by a 1 dimensional array?    stackoverflow.com

You have an array of shape (a,b,c) and you want to multiply the second dimension by an array of shape (b) A for loop would work, but is there a better way? Ex. ...

5. How to restore a 2-dimensional numpy.array from a bytestring?    stackoverflow.com

numpy.array has a handy .tostring() method which produces a compact representation of the array as a bytestring. But how do I restore the original array from the bytestring? numpy.fromstring() only produces ...

6. Dynamic Access of Multi dimensional Python Array    stackoverflow.com

I am a python newbie. I was confused on how to access array element dynamically. I have a list b= [1,2,5,8] that I dynamically obtain so its length can vary. With ...

7. Python Numpy 2-dimensional array iteration    stackoverflow.com

Would like to build a list of indices into a 2 dimensional bool_ array, where True.

import numpy
arr = numpy.zeros((6,6), numpy.bool_)
arr[2,3] = True
arr[5,1] = True
results1 = [[(x,y) for (y,cell) in enumerate(arr[x].flat) if ...