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Summary: 
How can you efficiently search an array to find the location of a certain item in it? 
Solution: 
The TableLookup() Cicode function can be used to search an array. Unfortunately, it only works for arrays of REAL (floating point) values. For INT or STRING arrays, custom Cicode will be needed. The simplest method is to use a FOR loop to check each element in the array and compare it with the desired value. This can be done with the linear search code below: //Searches gsSortArray for the sFind text and returns its element If the list is sorted (in alphabetical or numeric ordersee Q3750), it is much faster to use the binary search method. This algorithm looks at the middle item in the list. If it is greater than the item to find, the search is repeated on the first half of the list, otherwise the 2nd half of the list is checked. Each time the list is cut in half until only the desired item remains (or no item remains if the search item doesn't exist). With a linear search of 100 items, on average half of the items will be checked before a match is found and all items must be checked if there is no match. With a binary search of 100 items only 6 or 7 items will need to be checked. Since binary search requires that the list is sorted, it may not be the best choice if the list is constantly changing. Having to resort the list each time will cancel out the benefit of Binary Search. Although this binary search function is for strings, it can be used for numbers simply by changing the STRING variables to REAL or INT. GLOBAL STRING gsSortArray[479]; //Contains sorted list of strings to search // Search an ordered array for the first occurrence of the specified element WHILE (nHigh  nLow) > 1 DO IF (nHigh = nLast + 1) THEN 
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