diff --git a/_tools/algebra/scipySparseFromNgMatrix.py b/_tools/algebra/scipySparseFromNgMatrix.py
index 3a028e2fed8b2346de0bd75f5b0b792e5701e1e2..ce0795df62b9acafc7127b0e8de7bcacd5fc4659 100644
--- a/_tools/algebra/scipySparseFromNgMatrix.py
+++ b/_tools/algebra/scipySparseFromNgMatrix.py
@@ -7,7 +7,7 @@ def ScipySparseFromNgMatrix(a):
   import scipy.sparse as sp
 
   rows, cols, vals = a.mat.COO()
-  A = sp.csr_matrix( (vals.NumPy(), (rows, cols) ) )
+  A = sp.csr_matrix( (vals.NumPy(), (rows, cols) ), shape=(a.mat.height, a.mat.width) )
   return A