are numpy arrays columns or rows code example

Example 1: number of rows or columns in numpy ndarray python

# get number of rows in 2D numpy array.
numOfRows = np. size(arr2D, 0)
# get number of columns in 2D numpy array.
numOfColumns = np. size(arr2D, 1)

Example 2: get column or row of matrix array numpy python

test = numpy.array([[1, 2], [3, 4], [5, 6]])
column = test[:,0]
# column == array([1, 3, 5])
row = test[1,:]
# row == array([3, 4])