1 files changed, 57 insertions, 0 deletions
diff --git a/numpy/dual.py b/numpy/dual.py
new file mode 100644
index 000000000..c47f8f820
--- /dev/null
+++ b/numpy/dual.py
@@ -0,0 +1,57 @@
+# This module should be used for functions both in numpy and scipy if
+#  you want to use the numpy version if available but the scipy version
+#  otherwise.
+#  Usage  --- from numpy.dual import fft, inv
+
+__all__ = ['fft','ifft','fftn','ifftn','fft2','ifft2',
+           'norm','inv','svd','solve','det','eig','eigvals',
+           'eigh','eigvalsh','lstsq', 'pinv','cholesky','i0']
+
+import numpy.linalg as linpkg
+import numpy.fft as fftpkg
+from numpy.lib import i0
+import sys
+
+
+fft = fftpkg.fft
+ifft = fftpkg.ifft
+fftn = fftpkg.fftn
+ifftn = fftpkg.ifftn
+fft2 = fftpkg.fft2
+ifft2 = fftpkg.ifft2
+
+norm = linpkg.norm
+inv = linpkg.inv
+svd = linpkg.svd
+solve = linpkg.solve
+det = linpkg.det
+eig = linpkg.eig
+eigvals = linpkg.eigvals
+eigh = linpkg.eigh
+eigvalsh = linpkg.eigvalsh
+lstsq = linpkg.lstsq
+pinv = linpkg.pinv
+cholesky = linpkg.cholesky
+
+_restore_dict = {}
+
+def register_func(name, func):
+    if name not in __all__:
+        raise ValueError, "%s not a dual function." % name
+    f = sys._getframe(0).f_globals
+    _restore_dict[name] = f[name]
+    f[name] = func
+
+def restore_func(name):
+    if name not in __all__:
+        raise ValueError, "%s not a dual function." % name
+    try:
+        val = _restore_dict[name]
+    except KeyError:
+        return
+    else:
+        sys._getframe(0).f_globals[name] = val
+
+def restore_all():
+    for name in _restore_dict.keys():
+        restore_func(name)