1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
|
---
:name: dlassq
:md5sum: 3c1c556bdf9d5d6e44e32c35fd990d30
:category: :subroutine
:arguments:
- n:
:type: integer
:intent: input
- x:
:type: doublereal
:intent: input
:dims:
- n
- incx:
:type: integer
:intent: input
- scale:
:type: doublereal
:intent: input/output
- sumsq:
:type: doublereal
:intent: input/output
:substitutions: {}
:fortran_help: " SUBROUTINE DLASSQ( N, X, INCX, SCALE, SUMSQ )\n\n\
* Purpose\n\
* =======\n\
*\n\
* DLASSQ returns the values scl and smsq such that\n\
*\n\
* ( scl**2 )*smsq = x( 1 )**2 +...+ x( n )**2 + ( scale**2 )*sumsq,\n\
*\n\
* where x( i ) = X( 1 + ( i - 1 )*INCX ). The value of sumsq is\n\
* assumed to be non-negative and scl returns the value\n\
*\n\
* scl = max( scale, abs( x( i ) ) ).\n\
*\n\
* scale and sumsq must be supplied in SCALE and SUMSQ and\n\
* scl and smsq are overwritten on SCALE and SUMSQ respectively.\n\
*\n\
* The routine makes only one pass through the vector x.\n\
*\n\n\
* Arguments\n\
* =========\n\
*\n\
* N (input) INTEGER\n\
* The number of elements to be used from the vector X.\n\
*\n\
* X (input) DOUBLE PRECISION array, dimension (N)\n\
* The vector for which a scaled sum of squares is computed.\n\
* x( i ) = X( 1 + ( i - 1 )*INCX ), 1 <= i <= n.\n\
*\n\
* INCX (input) INTEGER\n\
* The increment between successive values of the vector X.\n\
* INCX > 0.\n\
*\n\
* SCALE (input/output) DOUBLE PRECISION\n\
* On entry, the value scale in the equation above.\n\
* On exit, SCALE is overwritten with scl , the scaling factor\n\
* for the sum of squares.\n\
*\n\
* SUMSQ (input/output) DOUBLE PRECISION\n\
* On entry, the value sumsq in the equation above.\n\
* On exit, SUMSQ is overwritten with smsq , the basic sum of\n\
* squares from which scl has been factored out.\n\
*\n\n\
* =====================================================================\n\
*\n"
|
