renamed folder 'code' to 'SimPEG'

new folder for ipython notebooks
improved 2D plots

SimPEG/EldadsCode/sputils.py

@@ -0,0 +1,77 @@
+from scipy import sparse
+from numpy import *
+
+
+def ddx(n):
+    """Define 1D derivatives"""
+    # ddx = lambda n: sparse.spdiags((np.ones((n+1, 1))*[-1, 1]).T, [0, 1], n, n+1, format='csr')
+    return sparse.spdiags(-ones(n), 0, n, n+1) + sparse.spdiags(ones(n+1), 1, n, n+1)
+
+
+def av(n):
+    """Define 1D average"""
+    return 0.5*(sparse.spdiags(ones(n+1), 0, n, n+1) + sparse.spdiags(ones(n+1), 1, n, n+1))
+
+
+def sdiag(h):
+    """Diagonal matrix"""
+    return sparse.spdiags(h, 0, size(h), size(h))
+
+
+def speye(n):
+    """sparse identity"""
+    return sparse.spdiags(ones(n), 0, n, n)
+
+
+def kron3(A, B, C):
+    """two kron prods"""
+    return sparse.kron(sparse.kron(A, B), C)
+
+
+def appendBottom(A, B):
+    """append on bottom"""
+    C = sparse.vstack((A, B))
+    C = C.tocsr()
+    return C
+
+
+def appendBottom3(A, B, C):
+    """append on bottom"""
+    C = appendBottom(appendBottom(A, B), C)
+    C = C.tocsr()
+    return C
+
+
+def appendRight(A, B):
+    """append on right"""
+    C = sparse.hstack((A, B))
+    C = C.tocsr()
+    return C
+
+
+def appendRight3(A, B, C):
+    """append on right"""
+    C = appendRight(appendRight(A, B), C)
+    C = C.tocsr()
+    return C
+
+
+def blkDiag(A, B):
+    """blockdigonal"""
+    O12 = sparse.coo_matrix((shape(A)[0], shape(B)[1]))
+    O21 = sparse.coo_matrix((shape(B)[0], shape(A)[1]))
+    C = sparse.vstack((sparse.hstack((A, O12)), sparse.hstack((O21, B))))
+    C = C.tocsr()
+    return C
+
+
+def blkDiag3(A, B, C):
+    """blockdigonal 3"""
+    ABC = blkDiag(blkDiag(A, B), C)
+    ABC = ABC.tocsr()
+    return ABC
+
+
+def spzeros(n1, n2):
+    """spzeros"""
+    return sparse.coo_matrix((n1, n2))