Merge pull request #27 from quackduck/master

Add option to set custom precision

asciigraph.go

@@ -11,7 +11,8 @@ import (
 func Plot(series []float64, options ...Option) string {
 	var logMaximum float64
 	config := configure(config{
-		Offset: 3,
+		Offset:    3,
+		Precision: 2,
 	}, options)
 
 	if config.Width > 0 {
@@ -59,7 +60,7 @@ func Plot(series []float64, options ...Option) string {
 		plot[i] = line
 	}
 
-	precision := 2
+	precision := config.Precision
 	logMaximum = math.Log10(math.Max(math.Abs(maximum), math.Abs(minimum))) //to find number of zeros after decimal
 	if minimum == float64(0) && maximum == float64(0) {
 		logMaximum = float64(-1)
@@ -69,9 +70,9 @@ func Plot(series []float64, options ...Option) string {
 		// negative log
 		if math.Mod(logMaximum, 1) != 0 {
 			// non-zero digits after decimal
-			precision += int(math.Abs(logMaximum))
+			precision += uint(math.Abs(logMaximum))
 		} else {
-			precision += int(math.Abs(logMaximum) - 1.0)
+			precision += uint(math.Abs(logMaximum) - 1.0)
 		}
 	} else if logMaximum > 2 {
 		precision = 0

asciigraph_test.go

@@ -213,6 +213,15 @@ func TestPlot(t *testing.T) {
  0.30 ┤ ╭╴
  0.20 ┤╭╯
  0.10 ┼╯`},
+		{
+			[]float64{-0.000018527, -0.021, -.00123, .00000021312, -.0434321234, -.032413241234, .0000234234},
+			[]Option{Height(5), Width(45), Precision(5)},
+			`  0.000023 ┼─╮           ╭────────╮                    ╭
+ -0.008467 ┤ ╰──╮     ╭──╯        ╰─╮                ╭─╯
+ -0.016958 ┤    ╰─────╯             ╰╮             ╭─╯
+ -0.025449 ┤                         ╰─╮         ╭─╯
+ -0.033940 ┤                           ╰╮   ╭────╯
+ -0.042430 ┼                            ╰───╯`},
 	}
 
 	for i := range cases {

cmd/asciigraph/main.go

@@ -16,6 +16,7 @@ var (
 	height             uint
 	width              uint
 	offset             uint = 3
+	precision          uint = 2
 	caption            string
 	enableRealTime     bool
 	realTimeDataBuffer int
@@ -33,6 +34,7 @@ func main() {
 	flag.UintVar(&height, "h", height, "`height` in text rows, 0 for auto-scaling")
 	flag.UintVar(&width, "w", width, "`width` in columns, 0 for auto-scaling")
 	flag.UintVar(&offset, "o", offset, "`offset` in columns, for the label")
+	flag.UintVar(&precision, "p", precision, "`precision` of data point labels along the y-axis")
 	flag.StringVar(&caption, "c", caption, "`caption` for the graph")
 	flag.BoolVar(&enableRealTime, "r", enableRealTime, "enables `realtime` graph for data stream")
 	flag.IntVar(&realTimeDataBuffer, "b", realTimeDataBuffer, "data points `buffer` when realtime graph enabled, default equal to `width`")
@@ -70,6 +72,7 @@ func main() {
 					asciigraph.Height(int(height)),
 					asciigraph.Width(int(width)),
 					asciigraph.Offset(int(offset)),
+					asciigraph.Precision(precision),
 					asciigraph.Caption(caption))
 				asciigraph.Clear()
 				fmt.Println(plot)
@@ -90,6 +93,7 @@ func main() {
 			asciigraph.Height(int(height)),
 			asciigraph.Width(int(width)),
 			asciigraph.Offset(int(offset)),
+			asciigraph.Precision(precision),
 			asciigraph.Caption(caption))
 
 		fmt.Println(plot)

options.go

@@ -14,6 +14,7 @@ type config struct {
 	Width, Height int
 	Offset        int
 	Caption       string
+	Precision     uint
 }
 
 // An optionFunc applies an option.
@@ -59,6 +60,11 @@ func Offset(o int) Option {
 	return optionFunc(func(c *config) { c.Offset = o })
 }
 
+// Precision sets the graphs precision.
+func Precision(p uint) Option {
+	return optionFunc(func(c *config) { c.Precision = p })
+}
+
 // Caption sets the graphs caption.
 func Caption(caption string) Option {
 	return optionFunc(func(c *config) {