feat: InDelta (#127)

compare/compare.go

@@ -10,6 +10,8 @@ import (
 	"time"
 
 	"github.com/duke-git/lancet/v2/convertor"
+	"github.com/duke-git/lancet/v2/mathutil"
+	"golang.org/x/exp/constraints"
 )
 
 // operator type
@@ -62,3 +64,8 @@ func LessOrEqual(left, right any) bool {
 func GreaterOrEqual(left, right any) bool {
 	return compareValue(greaterOrEqual, left, right)
 }
+
+// InDelta checks if two values are equal or not within a delta.
+func InDelta[T constraints.Integer | constraints.Float](left, right T, delta float64) bool {
+	return float64(mathutil.Abs(left-right)) <= delta
+}

compare/compare_example_test.go

@@ -168,3 +168,29 @@ func ExampleGreaterOrEqual() {
 	// false
 	// false
 }
+
+func ExampleInDelta() {
+	result1 := InDelta(1, 1, 0)
+	result2 := InDelta(1, 2, 0)
+
+	result3 := InDelta(2.0/3.0, 0.66667, 0.001)
+	result4 := InDelta(2.0/3.0, 0.0, 0.001)
+
+	result5 := InDelta(float64(74.96)-float64(20.48), 54.48, 0)
+	result6 := InDelta(float64(74.96)-float64(20.48), 54.48, 1e-14)
+
+	fmt.Println(result1)
+	fmt.Println(result2)
+	fmt.Println(result3)
+	fmt.Println(result4)
+	fmt.Println(result5)
+	fmt.Println(result6)
+
+	// Output:
+	// true
+	// false
+	// true
+	// false
+	// false
+	// true
+}

compare/compare_test.go

@@ -138,3 +138,19 @@ func TestGreaterOrEqual(t *testing.T) {
 	assert.Equal(false, GreaterOrEqual(int64(2), 1))
 	assert.Equal(false, GreaterOrEqual("b", "c"))
 }
+
+func TestInDelta(t *testing.T) {
+	t.Parallel()
+	assert := internal.NewAssert(t, "TestInDelta")
+
+	assert.Equal(true, InDelta(1, 1, 0))
+	assert.Equal(false, InDelta(1, 2, 0))
+
+	assert.Equal(true, InDelta(2.0/3.0, 0.66667, 0.001))
+	assert.Equal(false, InDelta(2.0/3.0, 0.0, 0.001))
+
+	assert.Equal(false, InDelta(float64(74.96)-float64(20.48), 54.48, 0))
+	assert.Equal(true, InDelta(float64(74.96)-float64(20.48), 54.48, 1e-14))
+	assert.Equal(false, InDelta(float64(float32(80.45)), float64(80.45), 0))
+	assert.Equal(true, InDelta(float64(float32(80.45)), float64(80.45), 1e-5))
+}