diff --git a/axis.go b/axis.go index 3f71451..762a6a2 100644 --- a/axis.go +++ b/axis.go @@ -63,6 +63,8 @@ type AxisOption struct { StrokeWidth float64 // The length of the axis tick TickLength int + // The first axis + FirstAxis int // The margin value of label LabelMargin int // The font size of label @@ -255,6 +257,7 @@ func (a *axisPainter) Render() (Box, error) { Length: tickLength, Unit: unit, Orient: orient, + First: opt.FirstAxis, }) p.LineStroke([]Point{ { @@ -273,6 +276,7 @@ func (a *axisPainter) Render() (Box, error) { Top: labelPaddingTop, Right: labelPaddingRight, })).MultiText(MultiTextOption{ + First: opt.FirstAxis, Align: textAlign, TextList: data, Orient: orient, diff --git a/examples/time_line_chart/main.go b/examples/time_line_chart/main.go new file mode 100644 index 0000000..10932cd --- /dev/null +++ b/examples/time_line_chart/main.go @@ -0,0 +1,82 @@ +package main + +import ( + "crypto/rand" + "fmt" + "io/ioutil" + "math/big" + "os" + "path/filepath" + "time" + + "github.com/vicanso/go-charts/v2" +) + +func writeFile(buf []byte) error { + tmpPath := "./tmp" + err := os.MkdirAll(tmpPath, 0700) + if err != nil { + return err + } + + file := filepath.Join(tmpPath, "time-line-chart.png") + err = ioutil.WriteFile(file, buf, 0600) + if err != nil { + return err + } + return nil +} + +func main() { + xAxisValue := []string{} + values := []float64{} + now := time.Now() + firstAxis := 0 + for i := 0; i < 300; i++ { + // 设置首个axis为xx:00的时间点 + if firstAxis == 0 && now.Minute() == 0 { + firstAxis = i + } + xAxisValue = append(xAxisValue, now.Format("15:04")) + now = now.Add(time.Minute) + value, _ := rand.Int(rand.Reader, big.NewInt(100)) + values = append(values, float64(value.Int64())) + } + p, err := charts.LineRender( + [][]float64{ + values, + }, + charts.TitleTextOptionFunc("Line"), + charts.XAxisDataOptionFunc(xAxisValue, charts.FalseFlag()), + charts.LegendLabelsOptionFunc([]string{ + "Demo", + }, "50"), + func(opt *charts.ChartOption) { + opt.XAxis.FirstAxis = firstAxis + // 必须要比计算得来的最小值更大(每60分钟) + opt.XAxis.SplitNumber = 60 + opt.Legend.Padding = charts.Box{ + Top: 5, + Bottom: 10, + } + opt.SymbolShow = charts.FalseFlag() + opt.LineStrokeWidth = 1 + opt.ValueFormatter = func(f float64) string { + return fmt.Sprintf("%.0f", f) + } + }, + ) + + if err != nil { + panic(err) + } + + buf, err := p.Bytes() + if err != nil { + panic(err) + } + err = writeFile(buf) + if err != nil { + panic(err) + } +} diff --git a/painter.go b/painter.go index 8f43940..18496fd 100644 --- a/painter.go +++ b/painter.go @@ -59,6 +59,8 @@ type PainterOptions struct { type PainterOption func(*Painter) type TicksOption struct { + // the first tick + First int Length int Orient string Count int @@ -74,6 +76,8 @@ type MultiTextOption struct { // The text rotation of label TextRotation float64 Offset Box + // The first text index + First int } type GridOption struct { @@ -616,6 +620,7 @@ func (p *Painter) Ticks(opt TicksOption) *Painter { return p } count := opt.Count + first := opt.First width := p.Width() height := p.Height() unit := 1 @@ -630,7 +635,10 @@ func (p *Painter) Ticks(opt TicksOption) *Painter { values = autoDivide(width, count) } for index, value := range values { - if index%unit != 0 { + if index < first { + continue + } + if (index-first)%unit != 0 { continue } if isVertical { @@ -688,7 +696,10 @@ func (p *Painter) MultiText(opt MultiTextOption) *Painter { isTextRotation := opt.TextRotation != 0 offset := opt.Offset for index, text := range opt.TextList { - if opt.Unit != 0 && index%opt.Unit != showIndex { + if index < opt.First { + continue + } + if opt.Unit != 0 && (index-opt.First)%opt.Unit != showIndex { continue } if isTextRotation { diff --git a/xaxis.go b/xaxis.go index 95578ff..61698d7 100644 --- a/xaxis.go +++ b/xaxis.go @@ -50,6 +50,8 @@ type XAxisOption struct { FontColor Color // The text rotation of label TextRotation float64 + // The first axis + FirstAxis int // The offset of label LabelOffset Box isValueAxis bool @@ -87,6 +89,7 @@ func (opt *XAxisOption) ToAxisOption() AxisOption { SplitLineColor: opt.Theme.GetAxisSplitLineColor(), TextRotation: opt.TextRotation, LabelOffset: opt.LabelOffset, + FirstAxis: opt.FirstAxis, } if opt.isValueAxis { axisOpt.SplitLineShow = true