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EdgeVector

Declaration: TMatrix.EdgeVector (Orient: TOrientation; EdgeOp: TEdgeOp; EdgeIx: TIntArray; var Dest: TVector): integer;
Depending on the parameter EdgeOp the method 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 matrix (version [1]). The results are stored in the vector Destvec, whose size is automatically adjusted to the corresponding edge of the matrix.

EdgeVector allows you to 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 MyMat.EdgeVector (orHoriz, eopSum, [], EdgeVec); is equivalent to MyMat.EdgeVector (orHoriz, eopSum, EdgeVec);. Please note that the indices of the columns and rows are 1-based.

The function in version [2] returns the following error codes:

 0 ... everything is OK
-1 ... the matrix 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 matrix MatA and stores them in the vector MVec:
MatA.EdgeVector (orVert, eopMean, [2,3,4,8,10], MVec);