diff --git a/math.go b/math.go
index f2860f5..6c1a1af 100644
--- a/math.go
+++ b/math.go
@@ -1,6 +1,8 @@
 package gmath
 
-import "math"
+import (
+	"math"
+)
 
 func Pow[N Number](x, y N) N {
 	return N(math.Pow(float64(x), float64(y)))
@@ -9,3 +11,15 @@ func Pow[N Number](x, y N) N {
 func Abs[N Number](v N) N {
 	return N(math.Abs(float64(v)))
 }
+
+func Mod[N Number](a, b N) N {
+	return N(math.Mod(float64(a), float64(b)))
+}
+
+func ModPositive[N Number](a, b N) N {
+	m := Mod(a, b)
+	if m >= 0 {
+		return m
+	}
+	return m + b
+}
diff --git a/math_test.go b/math_test.go
new file mode 100644
index 0000000..4731dd4
--- /dev/null
+++ b/math_test.go
@@ -0,0 +1,10 @@
+package gmath
+
+import (
+	"fmt"
+	"testing"
+)
+
+func TestMod(t *testing.T) {
+	fmt.Println(ModPositive(-1, 10))
+}