From bde6b04f7e3f29550a9db967ab929d589869c379 Mon Sep 17 00:00:00 2001 From: siddharth Date: Tue, 17 Aug 2021 20:24:26 -0400 Subject: lib: rng.go: remove MTSeed, MTExtract, and friends --- lib/rng.go | 46 ---------------------------------------------- 1 file changed, 46 deletions(-) (limited to 'lib') diff --git a/lib/rng.go b/lib/rng.go index 6f57324..94cbd6c 100644 --- a/lib/rng.go +++ b/lib/rng.go @@ -26,10 +26,6 @@ type MTRand struct { initialized bool } -// Stores state of MT19937 generator. -var mtGenSt []uint32 = make([]uint32, mtCoefN) -var mtIndex uint32 = mtCoefN + 1 - var mtLowerMask uint32 = (1 << mtCoefR) - 1 var mtUpperMask uint32 = 0xFFFFFFFF & (^mtLowerMask) @@ -43,15 +39,6 @@ func (r *MTRand) Seed(s uint32) { r.initialized = true } -func MTSeed(seed uint32) { - mtIndex = mtCoefN - mtGenSt[0] = seed - for i := uint32(1); i < mtCoefN; i++ { - mtGenSt[i] = (0xFFFFFFFF & - (mtF*(mtGenSt[i-1]^(mtGenSt[i-1]>>(mtCoefW-2))) + i)) - } -} - func (r *MTRand) Extract() uint32 { if !r.initialized || r.index >= mtCoefN { if !r.initialized { @@ -72,26 +59,6 @@ func (r *MTRand) Extract() uint32 { return y } -func MTExtract() uint32 { - if mtIndex >= mtCoefN { - if mtIndex > mtCoefN { - MTSeed(5489) - } - mtTwist() - } - - y := mtGenSt[mtIndex] - y = y ^ ((y >> mtCoefU) & mtCoefD) - y = y ^ ((y << mtCoefS) & mtCoefB) - y = y ^ ((y << mtCoefT) & mtCoefC) - y = y ^ (y >> mtCoefL) - - mtIndex = mtIndex + 1 - - r := 0xFFFFFFFF & y - return r -} - func (r *MTRand) twist() { for i := uint32(0); i < mtCoefN-1; i++ { x := (r.genSt[i] & mtUpperMask) + @@ -104,16 +71,3 @@ func (r *MTRand) twist() { } r.index = 0 } - -func mtTwist() { - for i := uint32(0); i < mtCoefN-1; i++ { - x := (mtGenSt[i] & mtUpperMask) + - (mtGenSt[(i+1)%mtCoefN] & mtLowerMask) - xA := x >> 1 - if x%2 != 0 { // lowest bit of x is 1 - xA = xA ^ mtCoefA - } - mtGenSt[i] = mtGenSt[(i+mtCoefM)%mtCoefN] ^ xA - } - mtIndex = 0 -} -- cgit v1.2.3