Add a "typecode" parameter to the identity() matrix function.

diff --git a/dunshire/matrices.py b/dunshire/matrices.py
index 6ed4f851487235dba117ef1521151bd432db9076..66c21768403f19e8affa18fe23d1ffdf4f0ecd16 100644 (file)
--- a/dunshire/matrices.py
+++ b/dunshire/matrices.py
@@ -209,7 +209,7 @@ def eigenvalues_re(anymat):
     return [eig.real for eig in eigs]
 
 
-def identity(domain_dim):
+def identity(domain_dim, typecode='i'):
     """
     Create an identity matrix of the given dimensions.
 
@@ -219,6 +219,10 @@ def identity(domain_dim):
     domain_dim : int
         The dimension of the vector space on which the identity will act.
 
+    typecode : {'i', 'd', 'z'}, optional
+        The type code for the returned matrix, defaults to 'i' for integers.
+        Can also be 'd' for real double, or 'z' for complex double.
+
     Returns
     -------
 
@@ -247,7 +251,7 @@ def identity(domain_dim):
     entries = [int(i == j)
                for i in range(domain_dim)
                for j in range(domain_dim)]
-    return matrix(entries, (domain_dim, domain_dim))
+    return matrix(entries, (domain_dim, domain_dim), tc=typecode)
 
 
 def inner_product(vec1, vec2):