1 dimensional array to 2 dimensional python code example

Example 1: python convert two dimensional list to one dimensional

# Python convert 2D into 1D array:

import itertools
x = [['foo'], ['bar', 'baz'], ['quux'], ("tup_1", "tup_2"), {1:"one", 2:"two"}]
print list(itertools.chain(*x))
print [element for sub in x for element in sub]

# Output:

['foo', 'bar', 'baz', 'quux', 'tup_1', 'tup_2', 1, 2]

Example 2: numpy convert 1d array to 2d

import numpy as np 

# 1D array 
one_dim_arr = np.array([1, 2, 3, 4, 5, 6])

# to convert to 2D array
# we can use the np.ndarray.reshape(shape) function 
# here shape is given by two integers seperated by a comma
# the two integers specify m,n for the new matrix 
# ensure that the matrix that you are trying to generate
# has a size that meets the number of elements in the 1D array. 
# for that make sure that 
# m * n = number of elements in the one dimentional array 

two_dim_arr = one_dim_arr.reshape(1, 6)

#which returns a 2D array
print(two_dim_arr)


# confirmed by the array.ndim attribute
print(two_dim_arr.ndim)

# you can even specify one of the dimensions as unknown by passing -1
# numpy will infer the length using the array and remaining dimensions

two_dim_arr = one_dim_arr.reshape(1,-1)

Example 3: python convert multidimensional array to one dimensional

In [12]: a = np.array([[1,2,3], [4,5,6]])

In [13]: b = a.ravel()

In [14]: b
Out[14]: array([1, 2, 3, 4, 5, 6])