Changeset 737

Timestamp:

07/31/14 11:08:02 (22 months ago)

Author:

mmckerns

Message:

simplified internal reducer state to always use arraylike; added wrap_reducer

Location:

mystic

Files:

• examples/test_wavy.py (modified) (3 diffs)
• mystic/abstract_solver.py (modified) (4 diffs)
• mystic/differential_evolution.py (modified) (2 diffs)
• mystic/tools.py (modified) (2 diffs)

mystic/examples/test_wavy.py

@@ -14 +14 @@
 from mystic.strategy import Best1Exp, Best1Bin, Rand1Exp
 from mystic.monitors import VerboseMonitor
-from mystic.tools import getch, reduced
+from mystic.tools import getch
 from numpy import arange
 from mystic.solvers import fmin
@@ -24 +24 @@
 from mystic.models import wavy1, wavy2
 wavy = wavy1
-
-# reduce wavy's multi-valued return
-#@reduced(sum, arraylike=True)
-def cost(x):
-    return wavy(x)
 
 def show():
@@ -67 +62 @@
     solver.SetGenerationMonitor(stepmon)
    #solver.SetReducer(sum, arraylike=True) # reduce wavy's multi-valued return
-    solver.Solve(cost, ChangeOverGeneration(generations=50), \
+    solver.Solve(wavy, ChangeOverGeneration(generations=50), \
                  strategy=strategy, CrossProbability=1.0, ScalingFactor=0.9, \
                  sigint_callback = plot_solution)

mystic/mystic/abstract_solver.py

@@ -78 +78 @@
 import numpy
 from numpy import inf, shape, asarray, absolute, asfarray
-from mystic.tools import wrap_function, wrap_nested
+from mystic.tools import wrap_function, wrap_nested, wrap_reducer
 from mystic.tools import wrap_bounds, wrap_penalty, reduced
 
@@ -146 +146 @@
         self._constraints     = lambda x: x
         self._penalty         = lambda x: 0.0
-        self._reducer         = (None, False)
+        self._reducer         = None
         self._cost            = (None, None)
         self._termination     = lambda x, *ar, **kw: False if len(ar) < 1 or ar[0] is False or kw.get('info',True) == False else '' #XXX: better default ?
@@ -220 +220 @@
       (e.g. lambda x,y: x+y), taking two scalars and producing a scalar."""
         if not reducer:
-            self._reducer = (None, True)
+            self._reducer = None
         elif not callable(reducer):
             raise TypeError, "'%s' is not a callable function" % reducer
-        else: #XXX: check for format: x' = reducer(x) ?
-            self._reducer = (reducer, arraylike) #XXX: bool(arraylike) ?
+        elif not arraylike:
+            self._reducer = wrap_reducer(reducer)   
+        else: #XXX: check if is arraylike?
+            self._reducer = reducer
         return
 
@@ -578 +580 @@
         cost = wrap_penalty(cost, self._penalty)
         cost = wrap_nested(cost, self._constraints)
-        if self._reducer[0]:
-            cost = reduced(*self._reducer)(cost) #XXX: decorated? as wrap_*?
+        if self._reducer:
+           #cost = reduced(*self._reducer)(cost) # was self._reducer = (f,bool)
+            cost = reduced(self._reducer, arraylike=True)(cost)
         # hold on to the 'wrapped' cost function
         self._cost = (cost, ExtraArgs)

mystic/mystic/differential_evolution.py

@@ -209 +209 @@
             cost = wrap_bounds(cost, self._strictMin, self._strictMax)
         cost = wrap_penalty(cost, self._penalty)
-        if self._reducer[0]:
-            cost = reduced(*self._reducer)(cost) #XXX: decorated? as wrap_*?
+        if self._reducer:
+           #cost = reduced(*self._reducer)(cost) # was self._reducer = (f,bool)
+            cost = reduced(self._reducer, arraylike=True)(cost)
         # hold on to the 'wrapped' cost function
         self._cost = (cost, ExtraArgs)
@@ -360 +361 @@
             cost = wrap_bounds(cost, self._strictMin, self._strictMax)
         cost = wrap_penalty(cost, self._penalty)
-        if self._reducer[0]:
-            cost = reduced(*self._reducer)(cost) #XXX: decorated? as wrap_*?
+        if self._reducer:
+           #cost = reduced(*self._reducer)(cost) # was self._reducer = (f,bool)
+            cost = reduced(self._reducer, arraylike=True)(cost)
         # hold on to the 'wrapped' cost function
         self._cost = (cost, ExtraArgs)

mystic/mystic/tools.py

@@ -25 +25 @@
         to a function object
     - wrap_bounds: impose bounds on a function object
+    - wrap_reducer: convert a reducer function to an arraylike interface
     - reduced: apply a reducer function to reduce output to a single value
     - unpair: convert a 1D array of N pairs to two 1D arrays of N values
@@ -183 +184 @@
             return target_function(x)
     return function_wrapper
+
+def wrap_reducer(reducer_function):
+    """convert a reducer function to an arraylike interface
+
+This is useful for converting a function that used python's 'y = reduce(f, x)'
+interface to an arraylike interface 'y = f(x)'.  Example usage...
+    >>> acum = wrap_reduce(numpy.add)
+    >>> acum([1,2,3,4])
+    10
+    >>> prod = wrap_reduce(lambda x,y: x*y)
+    >>> prod([1,2,3,4])
+    24
+    """
+    def _reduce(x): # NOTE: not a decorator
+        return reduce(reducer_function, x)
+    return _reduce
+
 
 def reduced(reducer=None, arraylike=False):