Reshaping a numpy array

Question

I have the following NumPy array,

[[date1,num1],[date2,num2],[date3,num3],[date4,num4]]

I want to divide it as follows:

[ [ [date1,num1],[date2,num2] ] , [ [date3,num3],[date4,num4] ] ]

Can anyone suggest something?

possible duplicate of [reshape an array in numpy](http://stackoverflow.com/questions/14476415/reshape-an-array-in-numpy) — Anderson Green, Feb 18 '15 at 20:17

score 0 · Accepted Answer · answered Feb 18 '15 at 20:21

0

a = np.array([['date1','num1'],['date2','num2'],['date3','num3'],['date4','num4']])

a.reshape((2,2,2))
array([[['date1', 'num1'],
    ['date2', 'num2']],

   [['date3', 'num3'],
    ['date4', 'num4']]])

answered Feb 18 '15 at 20:21

Aidan Kane

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i am a lil confused.... what if my array is [[date1,num1],[date2,num2],[date3,num3],[date4,num4],[date5,[num5],[date6],[num6]].. what parameter should i change? – gaurav gurnani Feb 18 '15 at 20:29

score 0 · Answer 2 · answered Feb 18 '15 at 20:28

You can use Numpy's reshape method and the -1 argument to reshape arrays of arbitrary length between the two forms you specify. Like so:

import numpy as np

#Generate an array of the form you specify of arbitrary length
arraylen = 10
a        = np.array([ ['date'+str(i),'num'+str(i)] for i in range(arraylen*2)])

#Reshape the array per your specifications
a.reshape((-1,2,2))

Gives

array([[['date0', 'num0'],
        ['date1', 'num1']],

       [['date2', 'num2'],
        ['date3', 'num3']],
        ...

Reshaping a numpy array

2 Answers2