Subroutine */
| 31592 | } /* dlasrt_ */ |
| 31593 | |
| 31594 | /* Subroutine */ int dlassq_(integer *n, doublereal *x, integer *incx, |
| 31595 | doublereal *scale, doublereal *sumsq) |
| 31596 | { |
| 31597 | /* System generated locals */ |
| 31598 | integer i__1, i__2; |
| 31599 | doublereal d__1; |
| 31600 | |
| 31601 | /* Local variables */ |
| 31602 | static integer ix; |
| 31603 | static doublereal absxi; |
| 31604 | |
| 31605 | |
| 31606 | /* |
| 31607 | -- LAPACK auxiliary routine (version 3.2) -- |
| 31608 | -- LAPACK is a software package provided by Univ. of Tennessee, -- |
| 31609 | -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- |
| 31610 | November 2006 |
| 31611 | |
| 31612 | |
| 31613 | Purpose |
| 31614 | ======= |
| 31615 | |
| 31616 | DLASSQ returns the values scl and smsq such that |
| 31617 | |
| 31618 | ( scl**2 )*smsq = x( 1 )**2 +...+ x( n )**2 + ( scale**2 )*sumsq, |
| 31619 | |
| 31620 | where x( i ) = X( 1 + ( i - 1 )*INCX ). The value of sumsq is |
| 31621 | assumed to be non-negative and scl returns the value |
| 31622 | |
| 31623 | scl = max( scale, abs( x( i ) ) ). |
| 31624 | |
| 31625 | scale and sumsq must be supplied in SCALE and SUMSQ and |
| 31626 | scl and smsq are overwritten on SCALE and SUMSQ respectively. |
| 31627 | |
| 31628 | The routine makes only one pass through the vector x. |
| 31629 | |
| 31630 | Arguments |
| 31631 | ========= |
| 31632 | |
| 31633 | N (input) INTEGER |
| 31634 | The number of elements to be used from the vector X. |
| 31635 | |
| 31636 | X (input) DOUBLE PRECISION array, dimension (N) |
| 31637 | The vector for which a scaled sum of squares is computed. |
| 31638 | x( i ) = X( 1 + ( i - 1 )*INCX ), 1 <= i <= n. |
| 31639 | |
| 31640 | INCX (input) INTEGER |
| 31641 | The increment between successive values of the vector X. |
| 31642 | INCX > 0. |
| 31643 | |
| 31644 | SCALE (input/output) DOUBLE PRECISION |
| 31645 | On entry, the value scale in the equation above. |
| 31646 | On exit, SCALE is overwritten with scl , the scaling factor |
| 31647 | for the sum of squares. |
| 31648 | |
| 31649 | SUMSQ (input/output) DOUBLE PRECISION |
| 31650 | On entry, the value sumsq in the equation above. |
| 31651 | On exit, SUMSQ is overwritten with smsq , the basic sum of |