[Scipy-svn] r2467 - trunk/Lib/optimize

[scipy-svn at scipy.org]

Author: timl
Date: 2006-12-26 19:16:03 -0600 (Tue, 26 Dec 2006)
New Revision: 2467

Modified:
   trunk/Lib/optimize/optimize.py
Log:
add an option to specify the initial direction set used in fmin_powell. fixes ticket #284

Modified: trunk/Lib/optimize/optimize.py
===================================================================
--- trunk/Lib/optimize/optimize.py	2006-12-27 01:01:53 UTC (rev 2466)
+++ trunk/Lib/optimize/optimize.py	2006-12-27 01:16:03 UTC (rev 2467)
@@ -1535,7 +1535,8 @@
 
 
 def fmin_powell(func, x0, args=(), xtol=1e-4, ftol=1e-4, maxiter=None,
-                maxfun=None, full_output=0, disp=1, retall=0, callback=None):
+                maxfun=None, full_output=0, disp=1, retall=0, callback=None,
+                direc=None):
     """Minimize a function using modified Powell's method.
 
     Description:
@@ -1551,6 +1552,7 @@
       callback -- an optional user-supplied function to call after each
                   iteration.  It is called as callback(xk), where xk is the
                   current parameter vector.
+      direc -- initial direction set
 
     Outputs: (xopt, {fopt, xi, direc, iter, funcalls, warnflag}, {allvecs})
 
@@ -1610,7 +1612,12 @@
     if maxfun is None:
         maxfun = N * 1000
 
-    direc = eye(N,dtype=float)
+
+    if direc is None:
+        direc = eye(N, dtype=float)
+    else:
+        direc = asarray(direc, dtype=float)
+
     fval = squeeze(func(x))
     x1 = x.copy()
     iter = 0;