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fix: ensure correct twiddle factor placement in fft/base/fftpack/sinqi #13459

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Merged
kgryte merged 1 commit into from
Jul 13, 2026
Merged

fix: ensure correct twiddle factor placement in fft/base/fftpack/sinqi #13459

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2 changes: 1 addition & 1 deletion lib/node_modules/@stdlib/fft/base/fftpack/sinqi/README.md
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Expand Up @@ -60,7 +60,7 @@ var cosineTable = workspace.slice( 0, N );
// returns <Float64Array>[ ~0.98, ~0.92, ~0.83, ~0.7, ~0.56, ~0.38, ~0.2, ~0.0 ]

var twiddleFactors = workspace.slice( 2*N, 3*N );
// returns <Float64Array>[ 0, ~0.707, ~0.707, 0, 0, 0, 0, 0 ]
// returns <Float64Array>[ ~0.707, ~0.707, 0, 0, 0, 0, 0, 0 ]

var factors = workspace.slice( 3*N, ( 3*N ) + 4 );
// returns <Float64Array>[ 8, 2, 2, 4 ]
Expand Down
4 changes: 2 additions & 2 deletions lib/node_modules/@stdlib/fft/base/fftpack/sinqi/benchmark/benchmark.js
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Expand Up @@ -53,12 +53,12 @@ function createBenchmark( N ) {
b.tic();
for ( i = 0; i < b.iterations; i++ ) {
sinqi( N, workspace, 1, 0 );
if ( isnan( workspace[ ( 2*N ) + 1 ] ) ) {
if ( isnan( workspace[ 2*N ] ) ) {
b.fail( 'should not return NaN' );
}
}
b.toc();
if ( isnan( workspace[ ( 2*N ) + 1 ] ) ) {
if ( isnan( workspace[ 2*N ] ) ) {
b.fail( 'should not return NaN' );
}
b.pass( 'benchmark finished' );
Expand Down
2 changes: 1 addition & 1 deletion lib/node_modules/@stdlib/fft/base/fftpack/sinqi/docs/repl.txt
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Expand Up @@ -51,7 +51,7 @@
> var cosineTable = workspace.slice( 0, N )
<Float64Array>[ ~0.98, ~0.92, ~0.83, ~0.7, ~0.56, ~0.38, ~0.2, ~0.0 ]
> var twiddleFactors = workspace.slice( 2*N, 3*N )
<Float64Array>[ 0, ~0.707, ~0.707, 0, 0, 0, 0, 0 ]
<Float64Array>[ ~0.707, ~0.707, 0, 0, 0, 0, 0, 0 ]
> var factors = workspace.slice( 3*N, ( 3*N ) + 4 )
<Float64Array>[ 8, 2, 2, 4 ]

Expand Down
2 changes: 1 addition & 1 deletion lib/node_modules/@stdlib/fft/base/fftpack/sinqi/docs/types/index.d.ts
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Expand Up @@ -51,7 +51,7 @@ import { Collection } from '@stdlib/types/array';
* // returns <Float64Array>[ ~0.98, ~0.92, ~0.83, ~0.7, ~0.56, ~0.38, ~0.2, ~0.0 ]
*
* var twiddleFactors = workspace.slice( 2*N, 3*N );
* // returns <Float64Array>[ 0, ~0.707, ~0.707, 0, 0, 0, 0, 0 ]
* // returns <Float64Array>[ ~0.707, ~0.707, 0, 0, 0, 0, 0, 0 ]
*
* var factors = workspace.slice( 3*N, ( 3*N ) + 4 );
* // returns <Float64Array>[ 8, 2, 2, 4 ]
Expand Down
2 changes: 1 addition & 1 deletion lib/node_modules/@stdlib/fft/base/fftpack/sinqi/lib/index.js
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Expand Up @@ -40,7 +40,7 @@
* // returns <Float64Array>[ ~0.98, ~0.92, ~0.83, ~0.7, ~0.56, ~0.38, ~0.2, ~0.0 ]
*
* var twiddleFactors = workspace.slice( 2*N, 3*N );
* // returns <Float64Array>[ 0, ~0.707, ~0.707, 0, 0, 0, 0, 0 ]
* // returns <Float64Array>[ ~0.707, ~0.707, 0, 0, 0, 0, 0, 0 ]
*
* var factors = workspace.slice( 3*N, ( 3*N ) + 4 );
* // returns <Float64Array>[ 8, 2, 2, 4 ]
Expand Down
2 changes: 1 addition & 1 deletion lib/node_modules/@stdlib/fft/base/fftpack/sinqi/lib/main.js
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Expand Up @@ -151,7 +151,7 @@ var cosqi = require( '@stdlib/fft/base/fftpack/cosqi' );
* // returns <Float64Array>[ ~0.98, ~0.92, ~0.83, ~0.7, ~0.56, ~0.38, ~0.2, ~0.0 ]
*
* var twiddleFactors = workspace.slice( 2*N, 3*N );
* // returns <Float64Array>[ 0, ~0.707, ~0.707, 0, 0, 0, 0, 0 ]
* // returns <Float64Array>[ ~0.707, ~0.707, 0, 0, 0, 0, 0, 0 ]
*
* var factors = workspace.slice( 3*N, ( 3*N ) + 4 );
* // returns <Float64Array>[ 8, 2, 2, 4 ]
Expand Down
2 changes: 1 addition & 1 deletion lib/node_modules/@stdlib/fft/base/fftpack/sinqi/test/fixtures/c/fftpack/large.json
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2 changes: 1 addition & 1 deletion lib/node_modules/@stdlib/fft/base/fftpack/sinqi/test/fixtures/c/fftpack/medium.json
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2 changes: 1 addition & 1 deletion lib/node_modules/@stdlib/fft/base/fftpack/sinqi/test/fixtures/c/fftpack/small.json
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@@ -1 +1 @@
{"lengths":[8,12,9,15,4,4,2,13,3,8],"offsets":[0,8,20,29,44,48,52,54,67,70],"cosines":[0.98078528040323043,0.92387953251128674,0.83146961230254524,0.70710678118654757,0.55557023301960229,0.38268343236508984,0.19509032201612833,6.123233995736766e-17,0.99144486137381038,0.96592582628906831,0.92387953251128674,0.86602540378443871,0.79335334029123528,0.70710678118654757,0.60876142900872066,0.50000000000000011,0.38268343236508984,0.25881904510252096,0.13052619222005171,6.123233995736766e-17,0.98480775301220802,0.93969262078590843,0.86602540378443871,0.76604444311897801,0.64278760968653936,0.50000000000000011,0.34202014332566882,0.17364817766693041,6.123233995736766e-17,0.99452189536827329,0.97814760073380569,0.95105651629515353,0.91354545764260087,0.86602540378443871,0.80901699437494745,0.74314482547739436,0.66913060635885824,0.58778525229247314,0.50000000000000011,0.40673664307580037,0.30901699437494745,0.20791169081775945,0.10452846326765368,6.123233995736766e-17,0.92387953251128674,0.70710678118654757,0.38268343236508984,6.123233995736766e-17,0.92387953251128674,0.70710678118654757,0.38268343236508984,6.123233995736766e-17,0.70710678118654757,6.123233995736766e-17,0.99270887409805397,0.97094181742605201,0.93501624268541483,0.88545602565320991,0.82298386589365646,0.74851074817110119,0.6631226582407953,0.56806474673115581,0.46472317204376862,0.35460488704253579,0.23931566428755782,0.12053668025532323,6.123233995736766e-17,0.86602540378443871,0.50000000000000011,6.123233995736766e-17,0.98078528040323043,0.92387953251128674,0.83146961230254524,0.70710678118654757,0.55557023301960229,0.38268343236508984,0.19509032201612833,6.123233995736766e-17],"twiddles":[0.70710678118654757,0.70710678118654746,0,0,0,0,0,0,0.86602540378443871,0.49999999999999994,0,0.50000000000000011,0.8660254037844386,0,6.123233995736766e-17,1,0,0,0,0,0.76604444311897801,0.64278760968653925,0,0.17364817766693041,0.98480775301220802,0,0,0,0,0.91354545764260087,0.40673664307580015,0.66913060635885824,0.74314482547739424,0,0.66913060635885824,0.74314482547739424,-0.10452846326765333,0.9945218953682734,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0.70710678118654757,0.70710678118654746,0,0,0,0,0,0]}
{"lengths":[2,2,15,8,8,4,9,6,15,15],"offsets":[0,2,4,19,27,35,39,48,54,69],"cosines":[0.70710678118654757,6.123233995736766e-17,0.70710678118654757,6.123233995736766e-17,0.99452189536827329,0.97814760073380569,0.95105651629515353,0.91354545764260087,0.86602540378443871,0.80901699437494745,0.74314482547739436,0.66913060635885824,0.58778525229247314,0.50000000000000011,0.40673664307580037,0.30901699437494745,0.20791169081775945,0.10452846326765368,6.123233995736766e-17,0.98078528040323043,0.92387953251128674,0.83146961230254524,0.70710678118654757,0.55557023301960229,0.38268343236508984,0.19509032201612833,6.123233995736766e-17,0.98078528040323043,0.92387953251128674,0.83146961230254524,0.70710678118654757,0.55557023301960229,0.38268343236508984,0.19509032201612833,6.123233995736766e-17,0.92387953251128674,0.70710678118654757,0.38268343236508984,6.123233995736766e-17,0.98480775301220802,0.93969262078590843,0.86602540378443871,0.76604444311897801,0.64278760968653936,0.50000000000000011,0.34202014332566882,0.17364817766693041,6.123233995736766e-17,0.96592582628906831,0.86602540378443871,0.70710678118654757,0.50000000000000011,0.25881904510252096,6.123233995736766e-17,0.99452189536827329,0.97814760073380569,0.95105651629515353,0.91354545764260087,0.86602540378443871,0.80901699437494745,0.74314482547739436,0.66913060635885824,0.58778525229247314,0.50000000000000011,0.40673664307580037,0.30901699437494745,0.20791169081775945,0.10452846326765368,6.123233995736766e-17,0.99452189536827329,0.97814760073380569,0.95105651629515353,0.91354545764260087,0.86602540378443871,0.80901699437494745,0.74314482547739436,0.66913060635885824,0.58778525229247314,0.50000000000000011,0.40673664307580037,0.30901699437494745,0.20791169081775945,0.10452846326765368,6.123233995736766e-17],"twiddles":[0,0,0,0,0.91354545764260087,0.40673664307580015,0.66913060635885824,0.74314482547739424,0,0.66913060635885824,0.74314482547739424,-0.10452846326765333,0.9945218953682734,0,0,0,0,0,0,0.70710678118654757,0.70710678118654746,0,0,0,0,0,0,0.70710678118654757,0.70710678118654746,0,0,0,0,0,0,0,0,0,0,0.76604444311897801,0.64278760968653925,0,0.17364817766693041,0.98480775301220802,0,0,0,0,0.50000000000000011,0.8660254037844386,0,0,0,0,0.91354545764260087,0.40673664307580015,0.66913060635885824,0.74314482547739424,0,0.66913060635885824,0.74314482547739424,-0.10452846326765333,0.9945218953682734,0,0,0,0,0,0,0.91354545764260087,0.40673664307580015,0.66913060635885824,0.74314482547739424,0,0.66913060635885824,0.74314482547739424,-0.10452846326765333,0.9945218953682734,0,0,0,0,0,0]}
22 changes: 11 additions & 11 deletions lib/node_modules/@stdlib/fft/base/fftpack/sinqi/test/test.js
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Expand Up @@ -117,9 +117,9 @@ tape( 'the function correctly initializes twiddle factors (small sequence length
workspace = new Float64Array( ( 3*N ) + 34 );
sinqi( N, workspace, 1, 0 );

t.strictEqual( workspace[ N ], 0.0, 'returns expected value' );
for ( i = 0; i < N-1; i++ ) {
y = workspace[ (2*N) + i + 1 ];
t.strictEqual( workspace[ (2*N) - 1 ], 0.0, 'returns expected value' );
for ( i = 0; i < N; i++ ) {
y = workspace[ (2*N) + i ];
e = expected[ off+i ];
t.strictEqual( isAlmostSameValue( y, e, ulps ), true, 'within '+ulps+' ULPs. N: '+N+'. y: '+y+'. E: '+e );
}
Expand Down Expand Up @@ -185,9 +185,9 @@ tape( 'the function correctly initializes twiddle factors (medium sequence lengt
workspace = new Float64Array( ( 3*N ) + 34 );
sinqi( N, workspace, 1, 0 );

t.strictEqual( workspace[ N ], 0.0, 'returns expected value' );
for ( i = 0; i < N-1; i++ ) {
y = workspace[ (2*N) + i + 1 ];
t.strictEqual( workspace[ (2*N) - 1 ], 0.0, 'returns expected value' );
for ( i = 0; i < N; i++ ) {
y = workspace[ (2*N) + i ];
e = expected[ off+i ];
t.strictEqual( isAlmostSameValue( y, e, ulps ), true, 'within '+ulps+' ULPs. N: '+N+'. y: '+y+'. E: '+e );
}
Expand Down Expand Up @@ -253,9 +253,9 @@ tape( 'the function correctly initializes twiddle factors (large sequence length
workspace = new Float64Array( ( 3*N ) + 34 );
sinqi( N, workspace, 1, 0 );

t.strictEqual( workspace[ N ], 0.0, 'returns expected value' );
for ( i = 0; i < N-1; i++ ) {
y = workspace[ (2*N) + i + 1 ];
t.strictEqual( workspace[ (2*N) - 1 ], 0.0, 'returns expected value' );
for ( i = 0; i < N; i++ ) {
y = workspace[ (2*N) + i ];
e = expected[ off+i ];
t.strictEqual( isAlmostSameValue( y, e, ulps ), true, 'within '+ulps+' ULPs. N: '+N+'. y: '+y+'. E: '+e );
}
Expand Down Expand Up @@ -307,8 +307,8 @@ tape( 'the function correctly handles stride and offset parameters', function te
expected = new Float64Array( ( 3*N ) + 34 );
sinqi( N, expected, 1, 0 );

for ( i = 0; i < N-1; i++ ) {
t.strictEqual( workspace[ offset + ( ( (2*N)+i+1 ) * stride ) ], expected[ (2*N)+i+1 ], 'returns expected value' );
for ( i = 0; i < N; i++ ) {
t.strictEqual( workspace[ offset + ( ( (2*N)+i ) * stride ) ], expected[ (2*N)+i ], 'returns expected value' );
}
t.end();
});