class_docstr: Test convolution_matrix vs. numpy.convolve for various parameters.
class_docstr_tok: ["Test","convolution_matrix","vs.","numpy.convolve","for","various","parameters","."]
code: def test_bad_n(self):
      # n must be a positive integer
      with pytest.raises(
          ValueError, match="n must be a positive integer"
      ):
          convolution_matrix([1, 2, 3], 0)
  
imports: import pytest
  import numpy
  from numpy import arange, array, eye, copy, sqrt
  from numpy.testing import assert_equal, assert_array_equal, assert_array_almost_equal, assert_allclose
  from pytest import raises
  from scipy.fft import fft
  from scipy.special import comb
  from scipy.linalg import toeplitz, hankel, circulant, hadamard, leslie, dft, companion, kron, block_diag, helmert, hilbert, invhilbert, pascal, invpascal, fiedler, fiedler_companion, eigvals, convolution_matrix
  from numpy.linalg import cond
label_desc: Use image node_id 2 for calling the TestConvolutionMatrix obj's underlying member method code with example usage: obj.test_bad_n() without return types