things work?

sequence/linear.go

@@ -2,12 +2,12 @@ package sequence
 
 // Values returns the array values of a linear sequence with a given start, end and optional step.
 func Values(start, end float64) []float64 {
-	return Seq{NewLinear().WithOffset(start).WithLimit(end).WithStep(1.0)}.Array()
+	return Seq{NewLinear().WithStart(start).WithEnd(end).WithStep(1.0)}.Array()
 }
 
 // ValuesWithStep returns the array values of a linear sequence with a given start, end and optional step.
 func ValuesWithStep(start, end, step float64) []float64 {
-	return Seq{NewLinear().WithOffset(start).WithLimit(end).WithStep(step)}.Array()
+	return Seq{NewLinear().WithStart(start).WithEnd(end).WithStep(step)}.Array()
 }
 
 // NewLinear returns a new linear generator.
@@ -17,30 +17,37 @@ func NewLinear() *Linear {
 
 // Linear is a stepwise generator.
 type Linear struct {
-	offset float64
+	start float64
-	limit  float64
+	end   float64
-	step   float64
+	step  float64
 }
 
 // Len returns the number of elements in the sequence.
 func (lg Linear) Len() int {
-	return (int((lg.limit - lg.offset) / lg.step)) + 1
+	if lg.start < lg.end {
+		return int((lg.end-lg.start)/lg.step) + 1
+	}
+	return int((lg.start-lg.end)/lg.step) + 1
 }
 
 // GetValue returns the value at a given index.
 func (lg Linear) GetValue(index int) float64 {
-	return lg.offset + (float64(index) * lg.step)
+	fi := float64(index)
+	if lg.start < lg.end {
+		return lg.start + (fi * lg.step)
+	}
+	return lg.start - (fi * lg.step)
 }
 
-// WithOffset sets the offset and returns the linear generator.
+// WithStart sets the start and returns the linear generator.
-func (lg *Linear) WithOffset(offset float64) *Linear {
+func (lg *Linear) WithStart(start float64) *Linear {
-	lg.offset = offset
+	lg.start = start
 	return lg
 }
 
-// WithLimit sets the step and returns the linear generator.
+// WithEnd sets the end and returns the linear generator.
-func (lg *Linear) WithLimit(limit float64) *Linear {
+func (lg *Linear) WithEnd(end float64) *Linear {
-	lg.limit = limit
+	lg.end = end
 	return lg
 }
 

sequence/linear_test.go

@@ -15,7 +15,7 @@ func TestValues(t *testing.T) {
 	assert.Equal(100, values[99])
 }
 
-func TestValueWithStep(t *testing.T) {
+func TestValuesWithStep(t *testing.T) {
 	assert := assert.New(t)
 
 	values := ValuesWithStep(0, 100, 5)
@@ -23,6 +23,11 @@ func TestValueWithStep(t *testing.T) {
 	assert.Len(values, 21)
 }
 
-func TestValuesLen(t *testing.T) {
+func TestValuesReversed(t *testing.T) {
 	assert := assert.New(t)
+
+	values := Values(10.0, 1.0)
+	assert.Equal(10, len(values))
+	assert.Equal(10.0, values[0])
+	assert.Equal(1.0, values[9])
 }

sequence/sequence.go

@@ -27,7 +27,6 @@ func (s Seq) Array() (output []float64) {
 		return
 	}
 
-	println(s.Len())
 	output = make([]float64, s.Len())
 	for i := 0; i < s.Len(); i++ {
 		output[i] = s.GetValue(i)

sequence/time_test.go

@@ -81,3 +81,31 @@ func TestSequenceHoursFill(t *testing.T) {
 
 	assert.NotZero(filledValues[16])
 }
+
+func TestTimeStart(t *testing.T) {
+	assert := assert.New(t)
+
+	times := []time.Time{
+		time.Now().AddDate(0, 0, -4),
+		time.Now().AddDate(0, 0, -2),
+		time.Now().AddDate(0, 0, -1),
+		time.Now().AddDate(0, 0, -3),
+		time.Now().AddDate(0, 0, -5),
+	}
+
+	assert.InTimeDelta(Time.Start(times), times[4], time.Millisecond)
+}
+
+func TestTimeEnd(t *testing.T) {
+	assert := assert.New(t)
+
+	times := []time.Time{
+		time.Now().AddDate(0, 0, -4),
+		time.Now().AddDate(0, 0, -2),
+		time.Now().AddDate(0, 0, -1),
+		time.Now().AddDate(0, 0, -3),
+		time.Now().AddDate(0, 0, -5),
+	}
+
+	assert.InTimeDelta(Time.End(times), times[2], time.Millisecond)
+}

stacked_bar_chart.go

@@ -202,7 +202,7 @@ func (sbc StackedBarChart) drawYAxis(r Renderer, canvasBox Box) {
 		r.LineTo(canvasBox.Right+DefaultHorizontalTickWidth, canvasBox.Bottom)
 		r.Stroke()
 
-		ticks := sequence.Seq{Provider: sequence.NewLinear().WithLimit(1.0).WithStep(0.2)}.Array()
+		ticks := sequence.ValuesWithStep(0.0, 1.0, 0.2)
 		for _, t := range ticks {
 			axisStyle.GetStrokeOptions().WriteToRenderer(r)
 			ty := canvasBox.Bottom - int(t*float64(canvasBox.Height()))

util/date_test.go

@@ -237,34 +237,6 @@ func TestDateIsNYSEHoliday(t *testing.T) {
 	assert.Equal(holidays, 55)
 }
 
-func TestTimeStart(t *testing.T) {
-	assert := assert.New(t)
-
-	times := []time.Time{
-		time.Now().AddDate(0, 0, -4),
-		time.Now().AddDate(0, 0, -2),
-		time.Now().AddDate(0, 0, -1),
-		time.Now().AddDate(0, 0, -3),
-		time.Now().AddDate(0, 0, -5),
-	}
-
-	assert.InTimeDelta(Date.Start(times), times[4], time.Millisecond)
-}
-
-func TestTimeEnd(t *testing.T) {
-	assert := assert.New(t)
-
-	times := []time.Time{
-		time.Now().AddDate(0, 0, -4),
-		time.Now().AddDate(0, 0, -2),
-		time.Now().AddDate(0, 0, -1),
-		time.Now().AddDate(0, 0, -3),
-		time.Now().AddDate(0, 0, -5),
-	}
-
-	assert.InTimeDelta(Date.End(times), times[2], time.Millisecond)
-}
-
 func TestDateDiffDays(t *testing.T) {
 	assert := assert.New(t)