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-rw-r--r--gcc-4.9/gcc/testsuite/go.test/test/bench/shootout/spectral-norm.go93
1 files changed, 93 insertions, 0 deletions
diff --git a/gcc-4.9/gcc/testsuite/go.test/test/bench/shootout/spectral-norm.go b/gcc-4.9/gcc/testsuite/go.test/test/bench/shootout/spectral-norm.go
new file mode 100644
index 000000000..6667f3e04
--- /dev/null
+++ b/gcc-4.9/gcc/testsuite/go.test/test/bench/shootout/spectral-norm.go
@@ -0,0 +1,93 @@
+/*
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+ * Redistributions of source code must retain the above copyright
+ notice, this list of conditions and the following disclaimer.
+
+ * Redistributions in binary form must reproduce the above copyright
+ notice, this list of conditions and the following disclaimer in the
+ documentation and/or other materials provided with the distribution.
+
+ * Neither the name of "The Computer Language Benchmarks Game" nor the
+ name of "The Computer Language Shootout Benchmarks" nor the names of
+ its contributors may be used to endorse or promote products derived
+ from this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE.
+*/
+
+/* The Computer Language Benchmarks Game
+ * http://shootout.alioth.debian.org/
+ *
+ * contributed by The Go Authors.
+ * Based on spectral-norm.c by Sebastien Loisel
+ */
+
+package main
+
+import (
+ "flag"
+ "fmt"
+ "math"
+)
+
+var n = flag.Int("n", 2000, "count")
+
+func evalA(i, j int) float64 { return 1 / float64(((i+j)*(i+j+1)/2 + i + 1)) }
+
+type Vec []float64
+
+func (v Vec) Times(u Vec) {
+ for i := 0; i < len(v); i++ {
+ v[i] = 0
+ for j := 0; j < len(u); j++ {
+ v[i] += evalA(i, j) * u[j]
+ }
+ }
+}
+
+func (v Vec) TimesTransp(u Vec) {
+ for i := 0; i < len(v); i++ {
+ v[i] = 0
+ for j := 0; j < len(u); j++ {
+ v[i] += evalA(j, i) * u[j]
+ }
+ }
+}
+
+func (v Vec) ATimesTransp(u Vec) {
+ x := make(Vec, len(u))
+ x.Times(u)
+ v.TimesTransp(x)
+}
+
+func main() {
+ flag.Parse()
+ N := *n
+ u := make(Vec, N)
+ for i := 0; i < N; i++ {
+ u[i] = 1
+ }
+ v := make(Vec, N)
+ for i := 0; i < 10; i++ {
+ v.ATimesTransp(u)
+ u.ATimesTransp(v)
+ }
+ var vBv, vv float64
+ for i := 0; i < N; i++ {
+ vBv += u[i] * v[i]
+ vv += v[i] * v[i]
+ }
+ fmt.Printf("%0.9f\n", math.Sqrt(vBv/vv))
+}