Changeset 853

Timestamp:

12/30/15 09:13:52 (5 months ago)

Author:

mmckerns

Message:

clarify 'combine' and provide new example using combine

Location:

mystic

Files:

• examples2/g01_alt2.py (added)
• mystic/constraints.py (modified) (3 diffs)
• tests/test_combine.py (modified) (2 diffs)

mystic/mystic/constraints.py

@@ -438 +438 @@
     args -- arguments for the penalty function [default: ()]
     kwds -- keyword arguments for the penalty function [default: {}]
-    k -- penalty multiplier
-    h -- iterative multiplier
+    k -- penalty multiplier [default: 1]
+    h -- iterative multiplier [default: 5]
+
+NOTE: The defaults provide a linear combination of the individual penalties
+    without any scaling. A different ptype (from 'mystic.penalty') will
+    apply a nonlinear scaling to the combined penalty, while a different
+    k will apply a linear scaling.
 
 NOTE: This function is also useful for combining constraints solvers
@@ -445 +450 @@
     Constraints solvers must first be converted to penalty functions
     (i.e. with 'as_penalty'), then combined, then can be converted to
-    a constraints solver (i.e. with `as_constraint'). The resulting
+    a constraints solver (i.e. with 'as_constraint'). The resulting
     constraints will likely be more expensive to evaluate and less
     accurate than writing the constraints solver from scratch.
@@ -453 +458 @@
    #if k is not None: settings['k'] = k
    #if h is not None: settings['h'] = h
+    k = settings.setdefault('k', 1)
+    if k is None: del settings['k']
     ptype = settings.pop('ptype', None)
     if ptype is None:

mystic/tests/test_combine.py

@@ -27 +27 @@
     p3 = lambda x: abs(x3 - f3(x))
     p = (p1,p2,p3)
-#   p = [ptype(pi)(lambda x:0.) for pi in p]
-#   ptype = None
-    penalty = combine(*p, k=k, ptype=ptype)
+    p = [ptype(pi)(lambda x:0.) for pi in p]
+    penalty = combine(*p, k=k)
     constraint = as_constraint(penalty, solver=solver)
 
@@ -55 +54 @@
     c = (c1,c2,c3)
     
+    k=1
     solver = 'buckshot' #'diffev'
     ptype = linear_equality #quadratic_equality
 
     p = [as_penalty(ci, ptype) for ci in c]
-    penalty = combine(*p, k=1, ptype=linear_equality)
+    penalty = combine(*p, k=k)
     constraint = as_constraint(penalty, solver=solver)