Skip to content

Commit 10e8866

Browse files
committed
feat: add lapack/base/dlascl
--- type: pre_commit_static_analysis_report description: Results of running static analysis checks when committing changes. report: - task: lint_filenames status: passed - task: lint_editorconfig status: passed - task: lint_markdown status: na - task: lint_package_json status: na - task: lint_repl_help status: na - task: lint_javascript_src status: passed - task: lint_javascript_cli status: na - task: lint_javascript_examples status: na - task: lint_javascript_tests status: na - task: lint_javascript_benchmarks status: na - task: lint_python status: na - task: lint_r status: na - task: lint_c_src status: na - task: lint_c_examples status: na - task: lint_c_benchmarks status: na - task: lint_c_tests_fixtures status: na - task: lint_shell status: na - task: lint_typescript_declarations status: na - task: lint_typescript_tests status: na - task: lint_license_headers status: passed ---
1 parent cb44d2a commit 10e8866

File tree

1 file changed

+285
-0
lines changed
  • lib/node_modules/@stdlib/lapack/base/dlascl/lib

1 file changed

+285
-0
lines changed
Lines changed: 285 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,285 @@
1+
/**
2+
* @license Apache-2.0
3+
*
4+
* Copyright (c) 2025 The Stdlib Authors.
5+
*
6+
* Licensed under the Apache License, Version 2.0 (the "License");
7+
* you may not use this file except in compliance with the License.
8+
* You may obtain a copy of the License at
9+
*
10+
* http://www.apache.org/licenses/LICENSE-2.0
11+
*
12+
* Unless required by applicable law or agreed to in writing, software
13+
* distributed under the License is distributed on an "AS IS" BASIS,
14+
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15+
* See the License for the specific language governing permissions and
16+
* limitations under the License.
17+
*/
18+
19+
/* eslint-disable max-statements, max-len */
20+
21+
'use strict';
22+
23+
// MODULES //
24+
25+
var isRowMajor = require( '@stdlib/ndarray/base/assert/is-row-major' );
26+
var abs = require( '@stdlib/math/base/special/abs' );
27+
var dlamch = require( '@stdlib/lapack/base/dlamch' );
28+
var loopOrder = require( '@stdlib/ndarray/base/nullary-loop-interchange-order' );
29+
var max = require( '@stdlib/math/base/special/fast/max' );
30+
var min = require( '@stdlib/math/base/special/fast/min' );
31+
32+
33+
// VARIABLES //
34+
35+
var smlnum = dlamch( 'safe minimum' );
36+
var bignum = 1.0 / smlnum;
37+
38+
39+
// MAIN //
40+
41+
/**
42+
* Performs a series of row interchanges on a matrix `A` using pivot indices stored in `IPIV`.
43+
*
44+
* @private
45+
* @param {string} type - specifies the type of matrix `A`
46+
* @param {NonNegativeInteger} KL - lower band width of `A`. Referenced only if type is `symmetric-banded-lower` or `banded`.
47+
* @param {NonNegativeInteger} KU - upper band width of `A`. Referenced only if type is `symmetric-banded-upper` or `banded`.
48+
* @param {number} CFROM - selected elements in `A` are multiplied by `CTO / CFROM`
49+
* @param {number} CTO - selected elements in `A` are multiplied by `CTO / CFROM`
50+
* @param {NonNegativeInteger} M - number of rows in matrix `A`
51+
* @param {NonNegativeInteger} N - number of columns in matrix `A`
52+
* @param {Float64Array} A - input matrix
53+
* @param {integer} strideA1 - stride of the first dimension of `A`
54+
* @param {integer} strideA2 - stride of the second dimension of `A`
55+
* @param {NonNegativeInteger} offsetA - starting index for `A`
56+
* @returns {Float64Array} scaled matrix `A`
57+
*
58+
* @example
59+
* var Float64Array = require( '@stdlib/array/float64' );
60+
*
61+
* var A = new Float64Array( [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0 ] ); // => [ [ 1.0, 2.0 ], [ 3.0, 4.0 ], [ 5.0, 6.0 ] ]
62+
*
63+
* dlascl( 'general', 0, 0, 1.0, 2.0, 3, 2, A, 2, 1, 0 );
64+
* // A => <Float64Array>[ 2.0, 4.0, 6.0, 8.0, 10.0, 12.0 ]
65+
*/
66+
function dlascl( type, KL, KU, CFROM, CTO, M, N, A, strideA1, strideA2, offsetA ) { // eslint-disable-line max-params
67+
var cfromc;
68+
var cfrom1;
69+
var ctoc;
70+
var cto1;
71+
var done;
72+
var mul;
73+
var da1;
74+
var da0;
75+
var S1;
76+
var S0;
77+
var ia;
78+
var i0;
79+
var i1;
80+
var k3;
81+
var k4;
82+
var k1;
83+
var k2;
84+
var sh;
85+
var sa;
86+
var o;
87+
88+
if ( N === 0 || M === 0 ) {
89+
return A;
90+
}
91+
92+
done = false;
93+
94+
cfromc = CFROM;
95+
ctoc = CTO;
96+
97+
while ( !done ) {
98+
cfrom1 = CTO * smlnum;
99+
if ( cfrom1 === cfromc ) {
100+
// cfromc is Infinity, multiply by a correctly signed zero for finite ctoc or NaN
101+
mul = ctoc / cfromc;
102+
done = true;
103+
cto1 = ctoc;
104+
} else {
105+
cto1 = ctoc / bignum;
106+
if ( cto1 === ctoc ) {
107+
// ctoc is either zero or Infinity, thus ctoc itself is a correct multiplication factor
108+
mul = ctoc;
109+
done = true;
110+
cfromc = 1.0;
111+
} else if ( abs( cfrom1 ) > abs( ctoc ) && ctoc !== 0.0 ) {
112+
mul = smlnum;
113+
done = false;
114+
ctoc = cto1;
115+
} else if ( abs( cto1 ) > abs( cfromc ) ) {
116+
mul = bignum;
117+
done = false;
118+
ctoc = cto1;
119+
} else {
120+
mul = ctoc / cfromc;
121+
done = true;
122+
}
123+
}
124+
125+
if ( type === 'general' ) {
126+
// Full matrix
127+
128+
// Resolve the loop interchange order:
129+
o = loopOrder( [ M, N ], [ strideA1, strideA2 ] );
130+
sh = o.sh;
131+
sa = o.sx;
132+
133+
// Extract loop variables for purposes of loop interchange: dimensions and loop offset (pointer) increments...
134+
S0 = sh[ 0 ];
135+
S1 = sh[ 1 ];
136+
da0 = sa[ 0 ];
137+
da1 = sa[ 1 ] - ( S0*sa[0] );
138+
139+
// Set the pointers to the first indexed elements in the respective matrices...
140+
ia = offsetA;
141+
142+
// Iterate over the matrix dimensions...
143+
for ( i1 = 0; i1 < S1; i1++ ) {
144+
for ( i0 = 0; i0 < S0; i0++ ) {
145+
A[ ia ] *= mul;
146+
ia += da0;
147+
}
148+
ia += da1;
149+
}
150+
}
151+
152+
if ( type === 'upper' ) {
153+
// Upper triangular matrix
154+
ia = offsetA;
155+
if ( isRowMajor( [ strideA1, strideA2 ] ) ) {
156+
for ( i1 = 0; i1 < M; i1++ ) {
157+
for ( i0 = i1; i0 < N; i0++ ) {
158+
A[ ia+(i0*strideA2) ] *= mul;
159+
}
160+
ia += strideA1;
161+
}
162+
} else {
163+
for ( i1 = 0; i1 < N; i1++ ) {
164+
for ( i0 = 0; i0 <= min( i1, M-1 ); i0++ ) {
165+
A[ ia+(i0*strideA1) ] *= mul;
166+
}
167+
ia += strideA2;
168+
}
169+
}
170+
}
171+
172+
if ( type === 'lower' ) {
173+
// Lower triangular matrix
174+
ia = offsetA;
175+
if ( isRowMajor( [ strideA1, strideA2 ] ) ) {
176+
for ( i1 = 0; i1 < M; i1++ ) {
177+
for ( i0 = 0; i0 <= min( i1, N-1 ); i0++ ) {
178+
A[ ia+(i0*strideA2) ] *= mul;
179+
}
180+
ia += strideA1;
181+
}
182+
} else {
183+
for ( i1 = 0; i1 < N; i1++ ) {
184+
for ( i0 = i1; i0 < M; i0++ ) {
185+
A[ ia+(i0*strideA1) ] *= mul;
186+
}
187+
ia += strideA2;
188+
}
189+
}
190+
}
191+
192+
if ( type === 'upper-hessenberg' ) {
193+
if ( isRowMajor( [ strideA1, strideA2 ] ) ) {
194+
ia = offsetA;
195+
for ( i1 = 0; i1 < M; i1++ ) {
196+
for ( i0 = 0; i0 <= min( i1+1, N-1 ); i0++ ) {
197+
A[ ia+(i0*strideA2) ] *= mul;
198+
}
199+
ia += strideA1;
200+
}
201+
} else {
202+
ia = offsetA;
203+
for ( i0 = 0; i0 < N; i0++ ) {
204+
for ( i1 = 0; i1 <= min( i0+1, M-1 ); i1++ ) {
205+
A[ ia+(i1*strideA1) ] *= mul;
206+
}
207+
ia += strideA2;
208+
}
209+
}
210+
}
211+
212+
if ( type === 'symmetric-banded-lower' ) {
213+
if ( isRowMajor( [ strideA1, strideA2 ] ) ) {
214+
ia = offsetA;
215+
k3 = KL + 1;
216+
k4 = N;
217+
for ( i1 = 0; i1 < M; i1++ ) {
218+
for ( i0 = max( 0, i1 - KL ); i0 < min( k4, i1 + 1 ); i0++ ) {
219+
A[ ia+( ( i1-i0 ) * strideA2) ] *= mul;
220+
}
221+
ia += strideA1;
222+
}
223+
} else {
224+
ia = offsetA;
225+
for ( i1 = 0; i1 < N; i1++ ) {
226+
for ( i0 = 0; i0 < min( k3, k4 - i1 ); i0++ ) {
227+
A[ ia+(i0*strideA1) ] *= mul;
228+
}
229+
ia += strideA2;
230+
}
231+
}
232+
}
233+
234+
if ( type === 'symmetric-banded-upper' ) {
235+
k1 = KU + 1;
236+
ia = offsetA;
237+
238+
if ( isRowMajor( [ strideA1, strideA2 ] ) ) {
239+
for ( i1 = 0; i1 < M; i1++ ) {
240+
for ( i0 = i1; i0 < min( N, i1 + k1 ); i0++ ) {
241+
A[ ia + ( (i0-i1) * strideA2) ] *= mul;
242+
}
243+
ia += strideA1;
244+
}
245+
} else {
246+
for ( i1 = 0; i1 < N; i1++ ) {
247+
for ( i0 = max( k1 - i1, 0 ); i0 < k1; i0++ ) {
248+
A[ ia+(i0*strideA1) ] *= mul;
249+
}
250+
ia += strideA2;
251+
}
252+
}
253+
}
254+
255+
if ( type === 'banded' ) {
256+
k1 = KL + KU + 2;
257+
k2 = KL + 1;
258+
k3 = ( 2 * KL ) + KU + 1;
259+
k4 = KL + KU + 1 + M;
260+
ia = offsetA;
261+
if ( isRowMajor( [ strideA1, strideA2 ] ) ) {
262+
for ( i1 = 0; i1 < M; i1++ ) {
263+
for ( i0 = max( 0, i1 - KL ); i0 <= min( N - 1, i1 + KU ); i0++ ) {
264+
A[ ia + ( ( i0 - i1 + KL ) * strideA2 ) ] *= mul;
265+
}
266+
ia += strideA1;
267+
}
268+
} else {
269+
for ( i1 = 0; i1 < N; i1++ ) {
270+
for ( i0 = max( k1 - i1, k2 ); i0 <= min( k3, k4-i1 ); i0++ ) {
271+
A[ ia+(i0*strideA1) ] *= mul;
272+
}
273+
ia += strideA2;
274+
}
275+
}
276+
}
277+
}
278+
279+
return A;
280+
}
281+
282+
283+
// EXPORTS //
284+
285+
module.exports = dlascl;

0 commit comments

Comments
 (0)