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Diffstat (limited to 'PerformanceTests/SunSpider/tests/sunspider-0.9.1/math-spectral-norm.js')
-rw-r--r-- | PerformanceTests/SunSpider/tests/sunspider-0.9.1/math-spectral-norm.js | 51 |
1 files changed, 51 insertions, 0 deletions
diff --git a/PerformanceTests/SunSpider/tests/sunspider-0.9.1/math-spectral-norm.js b/PerformanceTests/SunSpider/tests/sunspider-0.9.1/math-spectral-norm.js new file mode 100644 index 0000000..8139ef3 --- /dev/null +++ b/PerformanceTests/SunSpider/tests/sunspider-0.9.1/math-spectral-norm.js @@ -0,0 +1,51 @@ +// The Great Computer Language Shootout +// http://shootout.alioth.debian.org/ +// +// contributed by Ian Osgood + +function A(i,j) { + return 1/((i+j)*(i+j+1)/2+i+1); +} + +function Au(u,v) { + for (var i=0; i<u.length; ++i) { + var t = 0; + for (var j=0; j<u.length; ++j) + t += A(i,j) * u[j]; + v[i] = t; + } +} + +function Atu(u,v) { + for (var i=0; i<u.length; ++i) { + var t = 0; + for (var j=0; j<u.length; ++j) + t += A(j,i) * u[j]; + v[i] = t; + } +} + +function AtAu(u,v,w) { + Au(u,w); + Atu(w,v); +} + +function spectralnorm(n) { + var i, u=[], v=[], w=[], vv=0, vBv=0; + for (i=0; i<n; ++i) { + u[i] = 1; v[i] = w[i] = 0; + } + for (i=0; i<10; ++i) { + AtAu(u,v,w); + AtAu(v,u,w); + } + for (i=0; i<n; ++i) { + vBv += u[i]*v[i]; + vv += v[i]*v[i]; + } + return Math.sqrt(vBv/vv); +} + +for (var i = 6; i <= 48; i *= 2) { + spectralnorm(i); +} |