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--- q [2009/08/06 14:40] – created clare
+++ q [2022/11/03 15:08] (current) – external edit 127.0.0.1
@@ Line 1: / Line 1: @@
+====== q ======
+**[//quick_refine// !E [//quick_refine_remove// !E]]**
+//quick_refine// removes parameters that influence <sub>{{techref_files:image002.gif?20x23}}</sub> in a small manner during a [[#k144|refinement cycle]]. Use of //quick_refine// speeds up simulated annealing, see for example the macro Auto_T which is used in example AE1-AUTO.INP. All refined parameters are reinstated for refinement at the start of subsequent cycles. Large //quick_refine// values aggressively removes parameters and convergence to low <sub>{{techref_files:image002.gif?20x23}}</sub> maybe hindered. A value of 0.1 works well.
+//quick_refine// has the following consequences:
+  * If parameters are not reinstated using //quick_refine_remove// then<sub>{{techref_files:image002.gif?20x23}}</sub> does not get to its lowest possible value for a particular refinement cycle.
+  * The degree of parameter randomization increases with increasing values of //quick_refine//. Thus randomization should be reduced as //quick_refine// increases. Alternatively //randomize_on_errros// can be used which automatically determines the amount a parameter is randomized.
+//quick_refine_remove//removes a parameter from refinement if it evaluates to non-zero or reinstates a parameter if it evaluates to zero. It can be a function of the reserved parameters QR_Removed or QR_Num_Times_Consecutively_Small and additionally global reserved parameter names such as Cycle_Iter, Cycle and T. If //quick_refine_remove// is not defined then the removal scheme of section 5.6 is used and parameters are not reinstated until the next refinement cycle.
+In most refinements the following will produce close to the lowest <sub>{{techref_files:image002.gif?20x23}}</sub> and in a shorter time period (see for example PAWLEY1.INP).
+quick_refine .1
+   quick_refine_remove =
+      IF QR_Removed THEN
+' reinstate the parameter
+      ELSE
+         IF QR_Num_Times_Consecutively_Small > 2 THEN
+' remove the parameter
+         ELSE
+' dont remove the parameter
+         ENDIF
+      ENDIF;