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-rw-r--r--PerformanceTests/SunSpider/tests/sunspider-0.9.1/math-spectral-norm.js51
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);
+}