REAL FUNCTION SCNRM2(N,CX,INCX)
 
a real function that computes the Euclidean norm of a complex
vector, also known as the root-mean-square norm, or the square root
of the sum of the squares of the entries.
SCNRM2:=SQRT(SUM(I=1 to N)REAL(CX(I))**2+AIMAG(CX(I))**2)
 
N      Input, INTEGER N, number of elements in vector.
 
SX     Input, COMPLEX SX(N), vector whose norm is desired.
 
INCX   Input, INTEGER INCX, increment between elements of SX.  For contiguous
       elements, INCX = 1.
 
SCNRM2 Output, REAL SCNRM2, the euclidean norm of the vector SX.