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EdgeVector

Declaration: EdgeVector (Src: TDouble2DArray; Orient: TOrientation; EdgeOp: TEdgeOp; EdgeIx: TIntArray; var Dest: TDoubleArray): integer;
Depending on the parameter EdgeOp the function EdgeVector calculates the minimum, the maximum, the sum, the mean or the standard deviation of all columns (Orient = orHoriz) or all rows (Orient = orVert) of the array Src. The results are stored in the array Dest, whose size is automatically adjusted to the corresponding edge of the Src array.

Further you can select specific columns or rows to be processed by storing the column/row indices in the array EdgeIx. Leaving the parameter EdgeIx empty (length = 0) is a shorthand notation for including all columns/rows. Thus, for example, the statement EdgeVector (MySrc, orHoriz, eopSum, [], EdgeVec); is equivalent to EdgeVector (MySrc, orHoriz, eopSum, EdgeVec);. Please note that the indices of the columns and rows are 0-based.

The function returns the following error codes:

 0 ... everything is OK
-1 ... Src has a dimension less than 1
-2 ... EdgeIx contains invalid column/row numbers

Example: The following statement calculates the means of the values in the columns 2,3,7,8 and 10 for all rows of the array MyArray and stores them in the array MyVec:
EdgeVector (MyArray, orVert, eopMean, [2,3,7,8,10], MyVec);