How to check if 2-D array is in another 2-D array

Question

consider the two dataframes df1 and df2 df1 = pd.DataFrame(np.zeros((6, 6)), list('abcdef'), list('abcdef'), dtype=int) df1.iloc[2:4, 2:4] = np.array([[1, 2], [3, 4]]) df1 df2 = pd.DataFrame(np.array([[1, 2], [3, 4]]), list('CD'), list('CD'), dtype=int) df2 It's clear that df2 is in df1. How do I test for this in general? JavaScript questions and answers, JavaScript questions pdf, JavaScript question bank, JavaScript questions and answers pdf, mcq on JavaScript pdf, JavaScript questions and solutions, JavaScript mcq Test , Interview JavaScript questions, JavaScript Questions for Interview, JavaScript MCQ (Multiple Choice Questions)

Answer 1

Assuming the dataframes contain 0's and 1s only, you can use 2D convolution and look if any element in the convoluted output is equal to the number of elements in df2 - from scipy.signal import convolve2d out = (convolve2d(df1,df2)==df2.size).any() For a generic case, let me use skimage module and this smart solution - from skimage.util import view_as_windows as viewW out = ((viewW(df1.values, df2.shape) == df2.values).all(axis=(2,3))).any() This is basically a template-matching problem and it has been discussed and we have gotten really efficient solutions under this post : How can I check if one two-dimensional NumPy array contains a specific pattern of values inside it?. That post also gives us the indices of all places in df1 where df2 could be located.