[Scipy-svn] r4170 - in trunk/scipy/interpolate: . tests

[scipy-svn at scipy.org]

Author: peridot
Date: 2008-04-23 20:19:57 -0500 (Wed, 23 Apr 2008)
New Revision: 4170

Modified:
   trunk/scipy/interpolate/info.py
   trunk/scipy/interpolate/interpolate.py
   trunk/scipy/interpolate/tests/test_interpolate.py
Log:
Fix, test, and publicize polynomial interpolation code


Modified: trunk/scipy/interpolate/info.py
===================================================================
--- trunk/scipy/interpolate/info.py	2008-04-24 00:31:58 UTC (rev 4169)
+++ trunk/scipy/interpolate/info.py	2008-04-24 01:19:57 UTC (rev 4170)
@@ -31,6 +31,11 @@
   interp2d -- Create a class whose instances can interpolate
                to compute unknown values of a bivariate function.
   Rbf -- Apply Radial Basis Functions to interpolate scattered N-D data.
+
+Additional tools
+
+  lagrange -- Compute the Lagrange interpolating polynomial
+
 """
 
 postpone_import = 1

Modified: trunk/scipy/interpolate/interpolate.py
===================================================================
--- trunk/scipy/interpolate/interpolate.py	2008-04-24 00:31:58 UTC (rev 4169)
+++ trunk/scipy/interpolate/interpolate.py	2008-04-24 01:19:57 UTC (rev 4170)
@@ -8,7 +8,7 @@
 
 from numpy import shape, sometrue, rank, array, transpose, \
      swapaxes, searchsorted, clip, take, ones, putmask, less, greater, \
-     logical_or, atleast_1d, atleast_2d, meshgrid, ravel, dot
+     logical_or, atleast_1d, atleast_2d, meshgrid, ravel, dot, poly1d
 import numpy as np
 import scipy.linalg as slin
 import scipy.special as spec

Modified: trunk/scipy/interpolate/tests/test_interpolate.py
===================================================================
--- trunk/scipy/interpolate/tests/test_interpolate.py	2008-04-24 00:31:58 UTC (rev 4169)
+++ trunk/scipy/interpolate/tests/test_interpolate.py	2008-04-24 01:19:57 UTC (rev 4170)
@@ -1,8 +1,8 @@
 from scipy.testing import *
-from numpy import mgrid, pi, sin, ogrid
+from numpy import mgrid, pi, sin, ogrid, poly1d
 import numpy as np
 
-from scipy.interpolate import interp1d, interp2d
+from scipy.interpolate import interp1d, interp2d, lagrange
 
 
 class TestInterp2D(TestCase):
@@ -198,6 +198,14 @@
                       [[4.8, 5.8], [15.6, 16.6]]]),
         )
 
+class TestLagrange(TestCase):
 
+    def test_lagrange(self):
+        p = poly1d([5,2,1,4,3])
+        xs = np.arange(len(p.coeffs))
+        ys = p(xs)
+        pl = lagrange(xs,ys)
+        assert_array_almost_equal(p.coeffs,pl.coeffs)
+
 if __name__ == "__main__":
     nose.run(argv=['', __file__])