Helper API refactor (#40)

* api cleaup

* updates

* wtf

* updates

* snapshot.

* tweaks

* snapshot

* api tweaks.

* updates

* updates

* updates

* changes.

* updates

* updates

* sequence => seq

* dont need to use curl, just using wget

* fixing examples

seq/sequence_test.go

@@ -0,0 +1,95 @@
+package seq
+
+import (
+	"testing"
+
+	assert "github.com/blendlabs/go-assert"
+)
+
+func TestSequenceEach(t *testing.T) {
+	assert := assert.New(t)
+
+	values := Seq{NewArray(1, 2, 3, 4)}
+	values.Each(func(i int, v float64) {
+		assert.Equal(i, v-1)
+	})
+}
+
+func TestSequenceMap(t *testing.T) {
+	assert := assert.New(t)
+
+	values := Seq{NewArray(1, 2, 3, 4)}
+	mapped := values.Map(func(i int, v float64) float64 {
+		assert.Equal(i, v-1)
+		return v * 2
+	})
+	assert.Equal(4, mapped.Len())
+}
+
+func TestSequenceFoldLeft(t *testing.T) {
+	assert := assert.New(t)
+
+	values := Seq{NewArray(1, 2, 3, 4)}
+	ten := values.FoldLeft(func(_ int, vp, v float64) float64 {
+		return vp + v
+	})
+	assert.Equal(10, ten)
+
+	orderTest := Seq{NewArray(10, 3, 2, 1)}
+	four := orderTest.FoldLeft(func(_ int, vp, v float64) float64 {
+		return vp - v
+	})
+	assert.Equal(4, four)
+}
+
+func TestSequenceFoldRight(t *testing.T) {
+	assert := assert.New(t)
+
+	values := Seq{NewArray(1, 2, 3, 4)}
+	ten := values.FoldRight(func(_ int, vp, v float64) float64 {
+		return vp + v
+	})
+	assert.Equal(10, ten)
+
+	orderTest := Seq{NewArray(10, 3, 2, 1)}
+	notFour := orderTest.FoldRight(func(_ int, vp, v float64) float64 {
+		return vp - v
+	})
+	assert.Equal(-14, notFour)
+}
+
+func TestSequenceSum(t *testing.T) {
+	assert := assert.New(t)
+
+	values := Seq{NewArray(1, 2, 3, 4)}
+	assert.Equal(10, values.Sum())
+}
+
+func TestSequenceAverage(t *testing.T) {
+	assert := assert.New(t)
+
+	values := Seq{NewArray(1, 2, 3, 4)}
+	assert.Equal(2.5, values.Average())
+
+	valuesOdd := Seq{NewArray(1, 2, 3, 4, 5)}
+	assert.Equal(3, valuesOdd.Average())
+}
+
+func TestSequenceVariance(t *testing.T) {
+	assert := assert.New(t)
+
+	values := Seq{NewArray(1, 2, 3, 4, 5)}
+	assert.Equal(2, values.Variance())
+}
+
+func TestSequenceNormalize(t *testing.T) {
+	assert := assert.New(t)
+
+	normalized := Values(1, 2, 3, 4, 5).Normalize().Array()
+
+	assert.NotEmpty(normalized)
+	assert.Len(normalized, 5)
+	assert.Equal(0, normalized[0])
+	assert.Equal(0.25, normalized[1])
+	assert.Equal(1, normalized[4])
+}