From 854ac4f8eaced83ee36dc5514bb303bad76e17c7 Mon Sep 17 00:00:00 2001
From: c9s <yoanlin93@gmail.com>
Date: Wed, 1 Feb 2023 18:56:01 +0800
Subject: [PATCH] grid2: fix pin price algorithm

---
 pkg/strategy/grid2/grid.go      |  9 ++++++---
 pkg/strategy/grid2/grid_test.go | 18 +++++++++---------
 2 files changed, 15 insertions(+), 12 deletions(-)

diff --git a/pkg/strategy/grid2/grid.go b/pkg/strategy/grid2/grid.go
index 792c1a334..d5615626c 100644
--- a/pkg/strategy/grid2/grid.go
+++ b/pkg/strategy/grid2/grid.go
@@ -35,11 +35,14 @@ type Pin fixedpoint.Value
 
 func calculateArithmeticPins(lower, upper, spread, tickSize fixedpoint.Value) []Pin {
 	var pins []Pin
+
+	// tickSize number is like 0.01, 0.1, 0.001
 	var ts = tickSize.Float64()
+	var prec = int(math.Round(math.Log10(ts) * -1.0))
+	var pow10 = math.Pow10(prec)
 	for p := lower; p.Compare(upper) <= 0; p = p.Add(spread) {
-		// tickSize here = 0.01
-		pp := p.Float64() / ts
-		pp = math.Round(pp) * ts
+		pp := math.Round(p.Float64()*pow10*10.0) / 10.0
+		pp = math.Trunc(pp) / pow10
 		pin := Pin(fixedpoint.NewFromFloat(pp))
 		pins = append(pins, pin)
 	}
diff --git a/pkg/strategy/grid2/grid_test.go b/pkg/strategy/grid2/grid_test.go
index a5d72281f..b5fdaff98 100644
--- a/pkg/strategy/grid2/grid_test.go
+++ b/pkg/strategy/grid2/grid_test.go
@@ -172,31 +172,31 @@ func Test_calculateArithmeticPins(t *testing.T) {
 				Pin(number(1000.0)),
 				Pin(number(1066.660)),
 				Pin(number(1133.330)),
-				Pin(number("1199.99")),
+				Pin(number("1200.00")),
 				Pin(number(1266.660)),
 				Pin(number(1333.330)),
-				Pin(number(1399.990)),
+				Pin(number(1400.000)),
 				Pin(number(1466.660)),
 				Pin(number(1533.330)),
-				Pin(number(1599.990)),
+				Pin(number(1600.000)),
 				Pin(number(1666.660)),
 				Pin(number(1733.330)),
-				Pin(number(1799.990)),
+				Pin(number(1800.000)),
 				Pin(number(1866.660)),
 				Pin(number(1933.330)),
-				Pin(number(1999.990)),
+				Pin(number(2000.000)),
 				Pin(number(2066.660)),
 				Pin(number(2133.330)),
-				Pin(number("2199.99")),
+				Pin(number("2200.00")),
 				Pin(number(2266.660)),
 				Pin(number(2333.330)),
-				Pin(number("2399.99")),
+				Pin(number("2400.00")),
 				Pin(number(2466.660)),
 				Pin(number(2533.330)),
-				Pin(number("2599.99")),
+				Pin(number("2600.00")),
 				Pin(number(2666.660)),
 				Pin(number(2733.330)),
-				Pin(number(2799.990)),
+				Pin(number(2800.000)),
 				Pin(number(2866.660)),
 				Pin(number(2933.330)),
 			},