python - SciPy Sparse Array: Get index for a data point -

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i creating csr sparse array (because have lot of empty elements/cells) need use forwards , backwards. is, need input 2 indices , element corresponds ( matrix[0][9]=34) need able indices upon knowing value 34. elements in array unique. have looked on answer regarding this, have not found one, or may have not understood looking if did! i'm quite new python, if make sure let me know functions find , steps retrieve indices element, appreciate it!

thanks in advance!

here's way of finding specific value applicable both numpy arrays , sparse matrices

in [119]: a=sparse.csr_matrix(np.arange(12).reshape(3,4))  in [120]: a==10 out[120]:  <3x4 sparse matrix of type '<class 'numpy.bool_'>'     1 stored elements in compressed sparse row format>  in [121]: (a==10).nonzero() out[121]: (array([2], dtype=int32), array([2], dtype=int32))  in [122]: (a.a==10).nonzero() out[122]: (array([2], dtype=int32), array([2], dtype=int32))

Comments

  1. Nishant Saurabh29 August 2026 at 10:34


    Excellent explanation! Simple, clear, and beginner-friendly. For anyone looking to learn more, check out Python-scipy-tutorial.

    ReplyDelete

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