doc: add doc for Log function

docs/mathutil.md

@@ -44,6 +44,7 @@ import (
 -   [LCM](#LCM)
 -   [Cos](#Cos)
 -   [Sin](#Sin)
+-   [Log](#Log)
 
 <div STYLE="page-break-after: always;"></div>
 
@@ -871,4 +872,40 @@ func main() {
     // 0
     // 1
 }
+```
+
+### <span id="Log">Log</span>
+
+<p>Returns the logarithm of base n.</p>
+
+<b>Signature:</b>
+
+```go
+func Log(n, base float64) float64
+```
+
+<b>Example:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "github.com/duke-git/lancet/v2/mathutil"
+)
+
+func main() {
+    result1 := mathutil.Log(8, 2)
+	result2 := mathutil.TruncRound(mathutil.Log(5, 2), 2)
+	result3 := mathutil.TruncRound(mathutil.Log(27, 3), 0)
+
+	fmt.Println(result1)
+	fmt.Println(result2)
+	fmt.Println(result3)
+
+	// Output:
+	// 3
+	// 2.32
+	// 3
+}
 ```

docs/mathutil_zh-CN.md

@@ -44,6 +44,7 @@ import (
 -   [LCM](#LCM)
 -   [Cos](#Cos)
 -   [Sin](#Sin)
+-   [Log](#Log)
 
 <div STYLE="page-break-after: always;"></div>
 
@@ -871,4 +872,39 @@ func main() {
     // 0
     // 1
 }
-```
+```
+
+### <span id="Log">Log</span>
+
+<p>计算以base为底n的对数。</p>
+
+<b>函数签名:</b>
+
+```go
+func Log(n, base float64) float64
+```
+
+<b>示例:</b>
+
+```go
+package main
+
+import (
+    "fmt"
+    "github.com/duke-git/lancet/v2/mathutil"
+)
+
+func main() {
+    result1 := mathutil.Log(8, 2)
+	result2 := mathutil.TruncRound(mathutil.Log(5, 2), 2)
+	result3 := mathutil.TruncRound(mathutil.Log(27, 3), 0)
+
+	fmt.Println(result1)
+	fmt.Println(result2)
+	fmt.Println(result3)
+
+	// Output:
+	// 3
+	// 2.32
+	// 3
+}

mathutil/mathutil.go

@@ -324,7 +324,7 @@ func Sin(radian float64, precision ...int) float64 {
 	return Cos((math.Pi / 2) - radian)
 }
 
-// Log retur the logarithm of base n.
+// Log returns the logarithm of base n.
 // Play: todo
 func Log(n, base float64) float64 {
 	return math.Log(n) / math.Log(base)