Added median.go (TheAlgorithms#522)

* Added Roundoff

Simple showcase of Roundoff operation in GoLang
feat: add roundoff.go
test: add roundoff_test.go
docs: added comments on both roundoff.go and roundoff_test.go

* Revert "Added Roundoff"

This reverts commit c50fa89.

* Added median.go

feat: added median.go
test: added median_test.go
docs: added comments on both median.go and median_test.go

* Performed suggested fixes and improvements on median.go and median_test.go

fix median.go on using switch case, formatting, applied generics
fix median_test.go on formatting and using edge case
doc median_test.go on comments for test cases

* Update to math/median.go

Co-authored-by: Taj <[email protected]>

* Revert "Update to math/median.go"

This reverts commit 7c7c4f5.

* Fix median.go

Fix: median.go (import local packages and rectify newly affected issues)

* Update median.go

Fix: median.go removed redundant codes

* Fix: median.go and median_test.go

Fix: median.go (removed all deemed irrelevant comments)
Fix: median.go (removed all deemed irrelevant comments and changed package + fixed newly affected issues)

* Update median.go

fix: median.go (return values directly)

Co-authored-by: Taj <[email protected]>

Author: jo3zeph

Diff for: go.sum

@@ -0,0 +1,28 @@
+// author(s) [jo3zeph](https://github.com/jo3zeph)
+// description: Find the median from a set of values
+// see median_test.go
+
+package math
+
+import (
+	"github.com/TheAlgorithms/Go/constraints"
+	"github.com/TheAlgorithms/Go/sort"
+)
+
+func Median[T constraints.Number](values []T) float64 {
+
+	sort.Bubble(values)
+
+	l := len(values)
+
+	switch {
+	case l == 0:
+		return 0
+
+	case l%2 == 0:
+		return float64((values[l/2-1] + values[l/2]) / 2)
+
+	default:
+		return float64(values[l/2])
+	}
+}

Diff for: math/median.go

@@ -0,0 +1,56 @@
+// author(s) [jo3zeph](https://github.com/jo3zeph)
+// median_test.go
+// see median.go
+
+package math_test
+
+import (
+	"testing"
+
+	"github.com/TheAlgorithms/Go/math"
+)
+
+func TestMedian(t *testing.T) {
+	testCases := []struct {
+		name       string
+		testValues []float64
+		answer     float64
+	}{
+
+		{
+			name:       "Series of numbers in ascending order",
+			testValues: []float64{12, 14, 16, 18, 19},
+			answer:     16,
+		},
+
+		{
+			name:       "Series of numbers in random order",
+			testValues: []float64{21, 10, 22, 33, 11, 88},
+			answer:     21.5,
+		},
+
+		{
+			name:       "Series of decimals in random order",
+			testValues: []float64{11.2, 32.5, 2.5, 37.8, 21.8, 5.2},
+			answer:     16.5,
+		},
+
+		{
+			testValues: []float64{},
+		},
+	}
+
+	for _, test := range testCases {
+		t.Run(test.name, func(t *testing.T) {
+
+			returnedMedian := math.Median(test.testValues)
+
+			t.Log(test.testValues, " ", returnedMedian)
+
+			if returnedMedian != test.answer {
+				t.Errorf("Test failed. Median should have been %v but received %v",
+					test.answer, returnedMedian)
+			}
+		})
+	}
+}