#include "blaswrap.h" #include "f2c.h" doublereal dzsum1_(integer *n, doublecomplex *cx, integer *incx) { /* -- LAPACK auxiliary routine (version 3.1) -- Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. November 2006 Purpose ======= DZSUM1 takes the sum of the absolute values of a complex vector and returns a double precision result. Based on DZASUM from the Level 1 BLAS. The change is to use the 'genuine' absolute value. Contributed by Nick Higham for use with ZLACON. Arguments ========= N (input) INTEGER The number of elements in the vector CX. CX (input) COMPLEX*16 array, dimension (N) The vector whose elements will be summed. INCX (input) INTEGER The spacing between successive values of CX. INCX > 0. ===================================================================== Parameter adjustments */ /* System generated locals */ integer i__1, i__2; doublereal ret_val; /* Builtin functions */ double z_abs(doublecomplex *); /* Local variables */ static integer i__, nincx; static doublereal stemp; --cx; /* Function Body */ ret_val = 0.; stemp = 0.; if (*n <= 0) { return ret_val; } if (*incx == 1) { goto L20; } /* CODE FOR INCREMENT NOT EQUAL TO 1 */ nincx = *n * *incx; i__1 = nincx; i__2 = *incx; for (i__ = 1; i__2 < 0 ? i__ >= i__1 : i__ <= i__1; i__ += i__2) { /* NEXT LINE MODIFIED. */ stemp += z_abs(&cx[i__]); /* L10: */ } ret_val = stemp; return ret_val; /* CODE FOR INCREMENT EQUAL TO 1 */ L20: i__2 = *n; for (i__ = 1; i__ <= i__2; ++i__) { /* NEXT LINE MODIFIED. */ stemp += z_abs(&cx[i__]); /* L30: */ } ret_val = stemp; return ret_val; /* End of DZSUM1 */ } /* dzsum1_ */