numpy.insert - This function inserts values in the input array along the given axis and before the given index. In this article we will discuss how to find index of a value in a Numpy array (both 1D & 2D) using numpy.where(). x, y and condition need to be broadcastable to some shape.. Returns: out: ndarray or tuple of ndarrays. NumPy is a powerful mathematical library of python which provides us with a function insert. Go to the editor. NumPy Array. If you want to find the index in Numpy array, then you can use the numpy.where() function. Parameters: condition: array_like, bool. If the given element doesn’t exist in numpy array then returned array of indices will be empty i.e. Find the index of value in Numpy Array using numpy.where(), Python : How to get the list of all files in a zip archive, Linux: Find files modified in last N minutes, Linux: Find files larger than given size (gb/mb/kb/bytes). The indexes in NumPy arrays start with 0, meaning that the first element has index 0, and the second has index 1 etc. Parameters: a: array_like. Returns: index_array: ndarray of ints. All rights reserved, Python: How To Find The Index of Value in Numpy Array. ... amax The maximum value along a given axis. Save my name, email, and website in this browser for the next time I comment. # Create a numpy array from a list of numbers arr = np.array([11, 12, 13, 14, 15, 16, 17, 15, 11, 12, 14, 15, 16, 17]) # Get the index of elements with value less than 16 and greater than 12 result = np.where((arr > 12) & (arr < 16)) print("Elements with value less than 16 and greater than 12 exists at following indices", result, sep='\n') So to get a list of exact indices, we can zip these arrays. Python’s numpy module provides a function to select elements based on condition. Python numpy.where(), elements of the NumPy array ndarray that satisfy the conditions can be replaced or performed specified processing. Values from which to choose. For example, get the indices of elements with value less than 16 and greater than 12 i.e. pos = np.where(elem == c) You can use this boolean index to check whether each item in an array with a condition. In the above small program, the .iloc gives the integer index and we can access the values of row and column by index values. for the i value, take all values (: is a full slice, from start to end) for the j value take 1; Giving this array [2, 5, 8]: The array you get back when you index or slice a numpy array is a view of the original array. By default, the index is into the flattened array, otherwise along the specified axis. Just wanted to say this page was EXTREMELY helpful for me. # app.py import numpy as np # Create a numpy array from a list of numbers arr = np.array([11, 19, 13, 14, 15, 11, 19, 21, 19, 20, 21]) result = np.where(arr == 19) print('Tuple of arrays returned: ', result) print("Elements with value 19 first exists at index:", result[0][0]) Output The result is a tuple of arrays (one for each axis) containing the indices where value 19 exists in the array. 32. The length of both the arrays will be the same. Input array. Similarly, the process is repeated for every index number. Learn how your comment data is processed. NumPy in python is a general-purpose array-processing package. Index.to_numpy(dtype=None, copy=False, na_value=