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shootout: make mandelbrot.go more like mandelbrot.c 

Surprise! The C code is using floating point values for its counters.
Its off the critical path, but the Go code and C code are supposed to
be as similar as possible to make comparisons meaningful.

It doesn't have a significant effect.

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/6260058
This commit is contained in:
Russ Cox 2012-05-30 14:40:59 -04:00
parent 3806cc7b05
commit eb056dbea7
1 changed files with 8 additions and 8 deletions
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16
test/bench/shootout/mandelbrot.go
View File

@ -50,21 +50,21 @@ func main() {
out := bufio.NewWriter(os.Stdout) out := bufio.NewWriter(os.Stdout)
defer out.Flush() defer out.Flush()
w := *n w := float64(*n)
h := *n h := float64(*n)
bit_num := 0 bit_num := 0
byte_acc := byte(0) byte_acc := byte(0)
const Iter = 50 const Iter = 50
const Zero float64 = 0 const Zero float64 = 0
const Limit = 2.0 const Limit = 2.0
fmt.Fprintf(out, "P4\n%d %d\n", w, h) fmt.Fprintf(out, "P4\n%d %d\n", *n, *n)
for y := 0; y < h; y++ { for y := 0.0; y < h; y++ {
for x := 0; x < w; x++ { for x := 0.0; x < w; x++ {
Zr, Zi, Tr, Ti := Zero, Zero, Zero, Zero Zr, Zi, Tr, Ti := Zero, Zero, Zero, Zero
Cr := (2*float64(x)/float64(w) - 1.5) Cr := (2*x/w - 1.5)
Ci := (2*float64(y)/float64(h) - 1.0) Ci := (2*y/h - 1.0)
for i := 0; i < Iter && (Tr+Ti <= Limit*Limit); i++ { for i := 0; i < Iter && (Tr+Ti <= Limit*Limit); i++ {
Zi = 2*Zr*Zi + Ci Zi = 2*Zr*Zi + Ci
@ -85,7 +85,7 @@ func main() {
byte_acc = 0 byte_acc = 0
bit_num = 0 bit_num = 0
} else if x == w-1 { } else if x == w-1 {
byte_acc <<= uint(8 - w%8) byte_acc <<= uint(8 - uint(*n)%8)
out.WriteByte(byte_acc) out.WriteByte(byte_acc)
byte_acc = 0 byte_acc = 0
bit_num = 0 bit_num = 0