Merge pull request #475 from QBatista/fix_error_lss

FIX: Raise correct error when `A` is not square in `LinearStateSpace`

Author: oyamad

quantecon/lss.py

@@ -110,16 +110,17 @@ def __init__(self, A, C, G, H=None, mu_0=None, Sigma_0=None):
         ni, nj = self.A.shape
         if ni != nj:
             raise ValueError(
-                "Matrix A (shape: %s) needs to be square" % (self.A.shape))
+                "Matrix A (shape: %s) needs to be square" % (self.A.shape, ))
         if ni != self.C.shape[0]:
             raise ValueError(
-                "Matrix C (shape: %s) does not have compatible dimensions with A. "
-                "It should be shape: %s" % (self.C.shape, (ni, 1)))
+                "Matrix C (shape: %s) does not have compatible dimensions "
+                "with A. It should be shape: %s" % (self.C.shape, (ni, 1)))
         self.m = self.C.shape[1]
         self.k, self.n = self.G.shape
         if self.n != ni:
-            raise ValueError("Matrix G (shape: %s) does not have compatible dimensions with A (%s)"%(
-                self.G.shape, self.A.shape))
+            raise ValueError("Matrix G (shape: %s) does not have compatible"
+                             "dimensions with A (%s)" % (self.G.shape,
+                                                         self.A.shape))
         if H is None:
             self.H = None
             self.l = None

quantecon/tests/test_lss.py

@@ -7,6 +7,7 @@
 import numpy as np
 from numpy.testing import assert_allclose
 from quantecon.lss import LinearStateSpace
+from nose.tools import raises
 
 
 class TestLinearStateSpace(unittest.TestCase):
@@ -65,6 +66,15 @@ def test_replicate_with_seed(self):
         assert_allclose(yval[0], expected_output)
 
 
+@raises(ValueError)
+def test_non_square_A():
+    A = np.zeros((1, 2))
+    C = np.zeros((1, 1))
+    G = np.zeros((1, 1))
+
+    LinearStateSpace(A, C, G)
+
+
 if __name__ == '__main__':
     suite = unittest.TestLoader().loadTestsFromTestCase(TestLinearStateSpace)
     unittest.TextTestRunner(verbosity=2, stream=sys.stderr).run(suite)