How to check sparse matrix in python
I have a matrix and I want to check if it is sparse or not. Show Things I have tried:
This works fine if I know exactly which sparse class I want to check.
But I want a way to know if matrix is sparse or not, and should work irrespective of which sparse class. Kindly help me. asked Mar 8, 2016 at 18:06
answered Mar 8, 2016 at 18:44
BoaBoa 2,5341 gold badge21 silver badges37 bronze badges You can do sparsity = 1.0 - count_nonzero(X) / X.size This works for any matrices. answered Mar 16, 2020 at 3:50
Not the answer you're looking for? Browse other questions tagged python class matrix sparse-matrix or ask your own question.View Discussion Improve Article Save Article View Discussion Improve Article Save Article A matrix is a two-dimensional data object having m rows and n columns, therefore a total of m*n values. If most of the values of a matrix are 0 then
we say that the matrix is sparse. Examples: Input : 1 0 3 0 0 4 6 0 0 Output : Yes There are 5 zeros. This count is more than half of matrix size. Input : 1 2 3 0 7 8 5 0 7 Output: No To check whether a matrix is a sparse matrix, we only need to check the total number of elements that are equal to zero. If this count is more than (m * n)/2, we return true. Implementation: C++
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Time Complexity: O(m*n) This article is contributed by Aarti_Rathi and Vineet Joshi. If you like GeeksforGeeks and would like to contribute, you can also write an article using write.geeksforgeeks.org or mail your article to . See your article appearing on the GeeksforGeeks main page and help other Geeks. How do you check if a matrix is sparse or not?The definition of a sparse matrix is, if the 2/3rd of the elements are 0, then the matrix is denoted as a sparse matrix. Here is the example of a sparse matrix. To check it, we will count the number of 0s in the matrix, then if that count is greater than 2/3rd of the total elements, then this is sparse.
How do you find the sparsity of a matrix?The number of zero-valued elements divided by the total number of elements (e.g., m × n for an m × n matrix) is called the sparsity of the matrix (which is equal to 1 minus the density of the matrix).
How do you sparse a matrix in python?Sparse matrices in Python. import numpy as np.. from scipy. sparse import csr_matrix.. # create a 2-D representation of the matrix.. A = np. array([[1, 0, 0, 0, 0, 0], [0, 0, 2, 0, 0, 1],\. [0, 0, 0, 2, 0, 0]]). print("Dense matrix representation: \n", A). What does SciPy sparse Csr_matrix do?The function csr_matrix() is used to create a sparse matrix of compressed sparse row format whereas csc_matrix() is used to create a sparse matrix of compressed sparse column format.
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