basic question: how to sort

[urayasu]

Hi. Can anyone quickly teach me how to sort an array? (i.e. I want to transform x=[2,1,3,5] into x=[1,2,3,5] or x=[5,3,2,1]) Is there any intrinsic routine that does the job?

Thank you so much.

[pcurtis]

SUBROUTINE indexx (n,arrin,indx)
    IMPLICIT NONE
    INTEGER,INTENT(IN)                :: n
    REAL,INTENT(IN),DIMENSION(n)      :: arrin
    INTEGER,INTENT(OUT),DIMENSION(n)  :: indx
    INTEGER                           :: i,j,pivot,ir,indxt
    REAL                              :: q
    ! builds a sorted index array INDX of the
    ! N input elements in array ARRIN
    DO j = 1, n
        indx(j) = j
    END DO
    pivot  = n/2 + 1
    ir = n
10  IF (pivot > 1) THEN
	pivot    = pivot - 1
	indxt    = indx(pivot)
	q	     = arrin(indxt)
    ELSE
	indxt    = indx(ir)
	q        = arrin(indxt)
	indx(ir) = indx(1)
	ir       = ir-1
	IF (ir == 1) THEN
	    indx(1) = indxt
	    RETURN
	END IF
    END IF

    i = pivot
    j = pivot + pivot
20  IF (j <= ir) THEN
        IF (j < ir .AND. arrin(indx(j)) < arrin(indx(j+1))) j = j + 1
        IF (q < arrin(indx(j))) THEN
	    indx(i) = indx(j)
	    i = j
	    j = j + j
        ELSE
	    j = ir + 1
        END IF
        GOTO 20
    END IF
    indx(i) = indxt
    GO TO 10
END SUBROUTINE indexx

[Intel_C_Intel]

I don't know how big of sorting you need to do, but there is an excellent sorting & ranking package called ORDERPACK available for free. If you Google on ORDERPACK and sort you should find it.

HTH,
matt.