source: issm/oecreview/Archive/13393-13976/ISSM-13574-13575.diff@ 13980

Index: ../trunk-jpl/src/c/shared/Sorting/binary_search.cpp
===================================================================
--- ../trunk-jpl/src/c/shared/Sorting/binary_search.cpp (revision 13574)
+++ ../trunk-jpl/src/c/shared/Sorting/binary_search.cpp (revision 13575)
@@ -63,62 +63,49 @@
        /*Return result: */
        return found;
 } /*}}}*/
-int binary_search(int* poffset,double target,double* sorted_doubles,int num_doubles){ /*{{{*/
+int binary_search(int* poffset,double target,double* list,int num_doubles){ /*{{{*/
 
        /*output: */
-       int offset=0;  
-       int found=0; /*found=0: not found.   
-                                               found=1: found, and target is == to value at offset 
-                                               found=2: found, and target is > to value at offset  and < to value at offset+1
-                                               */
+       int offset = 0;
+       int found  = 0; /*found =  0: not found.
+                                                       found = -1: found, and target is < first element
+                                                       found =  1: found, and target is == to value at offset 
+                                                       found =  2: found, and target is > to value at offset  and < to value at offset+1
+                                                       found =  3: found, and target is >= last value */
 
        /*intermediary: */
-       double *beg = NULL;
-       double *end = NULL;
-       double *mid = NULL;
+       int n0 = 0;
+       int n1 = int(num_doubles/2);
+       int n2 = num_doubles-1;
 
-       // point to beginning and end of the array
-       beg = sorted_doubles;
-       end = sorted_doubles+num_doubles;
-       mid = beg+(int)(num_doubles/2.0);
-
-       if (target<*beg){
+       if(target<list[n0]){
+               found  = -1;
                offset = -1;
-               found  = 0;
        }
-       if (*beg==target){
-               found  = 1;
-               offset = 0;
+       else if(target>=list[n2]){
+               found  = 3;
+               offset = n2-1;
        }
-       else if(*(end-1)==target){
-               found  = 1;
-               offset = num_doubles-1;
-       }
        else{
-               while((beg <= end) && !( target>=*mid && target<*(mid+1)) ){
-                       // is the target in lower or upper half?
-                       if (target < *mid) {
-                               end = mid - 1;  //new end
-                               mid = beg + (end-beg)/2;  //new middle
+               while(!found){
+                       /*did we find the target?*/
+                       if(list[n1]<=target && list[n1+1]>target){
+                               found = 1;
+                               offset = n1;
+                               break;
                        }
-                       else {
-                               beg = mid + 1;  //new beginning
-                               mid = beg + (end-beg)/2;  //new middle
+                       if(target < list[n1]){
+                               n2 = n1;
+                               n1 = n0 + int((n2-n0)/2);
                        }
+                       else{
+                               n0 = n1;
+                               n1 = n0 + int((n2-n0)/2);
+                       }
                }
-                         
-               //did we find the target?
-               if( target>*mid &&  target<*(mid+1)){
-                       found=2;
-                       offset=mid-sorted_doubles;
-               }
-               else if( target==*mid){
-                       found=1;
-                       offset=mid-sorted_doubles;
-               }
-               else {
-                       found=0;
-               }
+
+               //did we find an exact target?
+               if(list[n1]==target) found = 2;
        }
 
        /*Assign output pointers:*/