Adding a Counter class

Counter.go

@@ -0,0 +1,37 @@
+package statistics
+
+//Counter counter
+type Counter struct {
+	sample []float64
+	data   map[float64]int
+}
+
+//NewCounter initializae a Counter
+func NewCounter(sample []float64) Counter {
+	counter := Counter{}
+	counter.sample = sample
+	counter.data = map[float64]int{}
+	make(counter)
+
+	return counter
+}
+
+func make(counter Counter) {
+	for _, key := range counter.sample {
+		if _, ok := counter.data[key]; ok {
+			counter.data[key]++
+		} else {
+			counter.data[key] = 1
+		}
+	}
+}
+
+//Values Return the Values counted
+func (counter Counter) Values() []int {
+	values := []int{}
+	for _, value := range counter.data {
+		values = append(values, value)
+	}
+	return values
+
+}

counter_test.go

@@ -0,0 +1,23 @@
+package statistics
+
+import (
+	"reflect"
+	"testing"
+)
+
+func TestValues(t *testing.T) {
+	cases := []struct {
+		sample []float64
+		wanted []int
+	}{
+		{[]float64{1.0, 1.0}, []int{2}},
+		{[]float64{1.0, 2.0}, []int{1, 1}},
+		{[]float64{}, []int{}},
+	}
+	for _, c := range cases {
+		got := NewCounter(c.sample).Values()
+		if !reflect.DeepEqual(got, c.wanted) {
+			t.Errorf("Counter.values(%v) want: %v; got %v", c.sample, c.wanted, got)
+		}
+	}
+}