Add pure python prototype for BLOCKDIAG projector.

wrapper/python/pyfaust/proj.py

@@ -379,4 +379,33 @@ class normlin(proj_gen):
         """
         self.constraint = ConstraintReal('normlin', shape[0], shape[1], s, normalized, pos)
 
+class blockdiag: # (proj_gen):
+
+
+    def __init__(self, shape, m_vec, n_vec):
+        self.m_vec = m_vec
+        self.n_vec = n_vec
+        self.shape = shape
+        if(m_vec[-1] != shape[0]): raise ValueError("The last index of (row"
+                                                    " offsets) m_vec"
+                                                    " must be equal to"
+                                                    " shape[0]")
+        if(n_vec[-1] != shape[1]): raise ValueError("The last index of (column"
+                                                    " offsets) n_vec"
+                                                    " must be equal to"
+                                                    " shape[1]")
+
+    def __call__(self, M):
+        if(M.shape != self.shape): raise ValueError('The dimension of the '
+                                                   'projector and matrix must '
+                                                   'agree.')
+        M_ = np.zeros(M.shape)
+        m_ = 0
+        n_ = 0
+        for i,(m,n) in enumerate(zip(self.m_vec, self.n_vec)):
+            print("i=", i, "m=", m, "n=", n)
+            M_[m_:m,n_:n] = M[m_:m,n_:n]
+            m_ = m
+            n_ = n
+        return M_