From 29ef238fa36f1997da7e8c56ae348b0c0c19015e Mon Sep 17 00:00:00 2001
From: Brian Tiger Chow <brian.holderchow@gmail.com>
Date: Mon, 15 Dec 2014 22:42:38 -0800
Subject: [PATCH] remove dead code

License: MIT
Signed-off-by: Brian Tiger Chow <brian@perfmode.com>
---
 exchange/bitswap/strategy/ledger.go    |  9 +++++++
 exchange/bitswap/strategy/math.go      | 34 --------------------------
 exchange/bitswap/strategy/math_test.go | 17 -------------
 3 files changed, 9 insertions(+), 51 deletions(-)
 delete mode 100644 exchange/bitswap/strategy/math.go
 delete mode 100644 exchange/bitswap/strategy/math_test.go

diff --git a/exchange/bitswap/strategy/ledger.go b/exchange/bitswap/strategy/ledger.go
index 684d383ef..649c1e73e 100644
--- a/exchange/bitswap/strategy/ledger.go
+++ b/exchange/bitswap/strategy/ledger.go
@@ -46,6 +46,15 @@ type ledger struct {
 	sentToPeer map[u.Key]time.Time
 }
 
+type debtRatio struct {
+	BytesSent uint64
+	BytesRecv uint64
+}
+
+func (dr *debtRatio) Value() float64 {
+	return float64(dr.BytesSent) / float64(dr.BytesRecv+1)
+}
+
 func (l *ledger) SentBytes(n int) {
 	l.exchangeCount++
 	l.lastExchange = time.Now()
diff --git a/exchange/bitswap/strategy/math.go b/exchange/bitswap/strategy/math.go
deleted file mode 100644
index c5339e5b3..000000000
--- a/exchange/bitswap/strategy/math.go
+++ /dev/null
@@ -1,34 +0,0 @@
-package strategy
-
-import (
-	"math"
-	"math/rand"
-)
-
-type strategyFunc func(*ledger) bool
-
-// TODO avoid using rand.Float64 method. it uses a singleton lock and may cause
-// performance issues. Instead, instantiate a rand struct and use that to call
-// Float64()
-func standardStrategy(l *ledger) bool {
-	return rand.Float64() <= probabilitySend(l.Accounting.Value())
-}
-
-func yesManStrategy(l *ledger) bool {
-	return true
-}
-
-func probabilitySend(ratio float64) float64 {
-	x := 1 + math.Exp(6-3*ratio)
-	y := 1 / x
-	return 1 - y
-}
-
-type debtRatio struct {
-	BytesSent uint64
-	BytesRecv uint64
-}
-
-func (dr *debtRatio) Value() float64 {
-	return float64(dr.BytesSent) / float64(dr.BytesRecv+1)
-}
diff --git a/exchange/bitswap/strategy/math_test.go b/exchange/bitswap/strategy/math_test.go
deleted file mode 100644
index 58092bc09..000000000
--- a/exchange/bitswap/strategy/math_test.go
+++ /dev/null
@@ -1,17 +0,0 @@
-package strategy
-
-import (
-	"testing"
-)
-
-func TestProbabilitySendDecreasesAsRatioIncreases(t *testing.T) {
-	grateful := debtRatio{BytesSent: 0, BytesRecv: 10000}
-	pWhenGrateful := probabilitySend(grateful.Value())
-
-	abused := debtRatio{BytesSent: 10000, BytesRecv: 0}
-	pWhenAbused := probabilitySend(abused.Value())
-
-	if pWhenGrateful < pWhenAbused {
-		t.Fail()
-	}
-}