hplot: add timeseries example with epok

Signed-off-by: Sebastien Binet <[email protected]>

go.mod

@@ -4,6 +4,7 @@ go 1.20
 
 require (
 	gioui.org v0.2.0
+	git.sr.ht/~sbinet/epok v0.1.0
 	git.sr.ht/~sbinet/go-arrow v0.2.0
 	github.com/astrogo/fitsio v0.3.0
 	github.com/campoy/embedmd v1.0.0
@@ -59,6 +60,7 @@ require (
 	github.com/posener/complete v1.2.3 // indirect
 	github.com/remyoudompheng/bigfft v0.0.0-20230129092748-24d4a6f8daec // indirect
 	github.com/rivo/uniseg v0.4.4 // indirect
+	github.com/teambition/rrule-go v1.8.2 // indirect
 	golang.org/x/exp/shiny v0.0.0-20230801115018-d63ba01acd4b // indirect
 	golang.org/x/mod v0.12.0 // indirect
 	golang.org/x/net v0.14.0 // indirect

go.sum

@@ -9,6 +9,8 @@ gioui.org/shader v1.0.6/go.mod h1:mWdiME581d/kV7/iEhLmUgUK5iZ09XR5XpduXzbePVM=
 gioui.org/x v0.2.0 h1:/MbdjKH19F16auv19UiQxli2n6BYPw7eyh9XBOTgmEw=
 gioui.org/x v0.2.0/go.mod h1:rCGN2nZ8ZHqrtseJoQxCMZpt2xrZUrdZ2WuMRLBJmYs=
 git.sr.ht/~sbinet/cmpimg v0.1.0 h1:E0zPRk2muWuCqSKSVZIWsgtU9pjsw3eKHi8VmQeScxo=
+git.sr.ht/~sbinet/epok v0.1.0 h1:gtcT69TjnNZl5NansTvzqWtIJ5W4ysMSyiZIjYDzORE=
+git.sr.ht/~sbinet/epok v0.1.0/go.mod h1:fPYSc65tPhuTrm4kYvAZDx/vGaMsbIGg7owyUn+DD48=
 git.sr.ht/~sbinet/gg v0.5.0 h1:6V43j30HM623V329xA9Ntq+WJrMjDxRjuAB1LFWF5m8=
 git.sr.ht/~sbinet/gg v0.5.0/go.mod h1:G2C0eRESqlKhS7ErsNey6HHrqU1PwsnCQlekFi9Q2Oo=
 git.sr.ht/~sbinet/go-arrow v0.2.0 h1:QIiVPcEtMb2lzOWDgBrIz9Sa+7Xvs2EJ/Icxe6IcUSI=
@@ -114,6 +116,8 @@ github.com/stretchr/testify v1.7.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/
 github.com/stretchr/testify v1.8.0/go.mod h1:yNjHg4UonilssWZ8iaSj1OCr/vHnekPRkoO+kdMU+MU=
 github.com/stretchr/testify v1.8.1 h1:w7B6lhMri9wdJUVmEZPGGhZzrYTPvgJArz7wNPgYKsk=
 github.com/stretchr/testify v1.8.1/go.mod h1:w2LPCIKwWwSfY2zedu0+kehJoqGctiVI29o6fzry7u4=
+github.com/teambition/rrule-go v1.8.2 h1:lIjpjvWTj9fFUZCmuoVDrKVOtdiyzbzc93qTmRVe/J8=
+github.com/teambition/rrule-go v1.8.2/go.mod h1:Ieq5AbrKGciP1V//Wq8ktsTXwSwJHDD5mD/wLBGl3p4=
 github.com/ulikunitz/xz v0.5.11 h1:kpFauv27b6ynzBNT/Xy+1k+fK4WswhN/6PN5WhFAGw8=
 github.com/ulikunitz/xz v0.5.11/go.mod h1:nbz6k7qbPmH4IRqmfOplQw/tblSgqTqBwxkY0oWt/14=
 github.com/xwb1989/sqlparser v0.0.0-20180606152119-120387863bf2 h1:zzrxE1FKn5ryBNl9eKOeqQ58Y/Qpo3Q9QNxKHX5uzzQ=

hplot/ticks_example_test.go

@@ -5,9 +5,13 @@
 package hplot_test
 
 import (
+	"image/color"
 	"log"
+	"time"
 
+	"git.sr.ht/~sbinet/epok"
 	"go-hep.org/x/hep/hplot"
+	"gonum.org/v1/plot/plotter"
 	"gonum.org/v1/plot/vg"
 	"gonum.org/v1/plot/vg/draw"
 )
@@ -75,3 +79,67 @@ func ExampleTicks() {
 		log.Fatalf("error: %+v\n", err)
 	}
 }
+
+func ExampleTicks_timeseries() {
+	cnv := epok.UTCUnixTimeConverter{}
+
+	p := hplot.New()
+	p.Title.Text = "Time series"
+	p.Y.Label.Text = "Goroutines"
+
+	p.Y.Min = 0
+	p.Y.Max = 4
+	p.X.AutoRescale = true
+	p.X.Tick.Marker = epok.Ticks{
+		Ruler: epok.Rules{
+			Major: epok.Rule{
+				Freq:  epok.Yearly,
+				Range: epok.Range{Step: 5},
+			},
+		},
+		Format:    "2006-01-02\n15:04:05",
+		Converter: cnv,
+	}
+
+	xysFrom := func(vs ...float64) plotter.XYs {
+		o := make(plotter.XYs, len(vs))
+		for i := range o {
+			o[i].X = vs[i]
+			o[i].Y = float64(i + 1)
+		}
+		return o
+	}
+	data := xysFrom(
+		cnv.FromTime(parse("2010-02-03 01:02:03")),
+		cnv.FromTime(parse("2015-02-03 04:05:06")),
+		cnv.FromTime(parse("2020-02-03 07:08:09")),
+	)
+
+	line, pnts, err := hplot.NewLinePoints(data)
+	if err != nil {
+		log.Fatalf("could not create plotter: %+v", err)
+	}
+
+	line.Color = color.RGBA{B: 255, A: 255}
+	pnts.Shape = draw.CircleGlyph{}
+	pnts.Color = color.RGBA{R: 255, A: 255}
+
+	p.Add(line, pnts, hplot.NewGrid())
+
+	err = p.Save(20*vg.Centimeter, 10*vg.Centimeter, "testdata/timeseries.png")
+	if err != nil {
+		log.Fatalf("could not save plot: %+v", err)
+	}
+}
+
+func parse(vs ...string) time.Time {
+	format := "2006-01-02 15:04:05"
+	if len(vs) > 1 {
+		format = vs[1]
+	}
+	t, err := time.Parse(format, vs[0])
+	if err != nil {
+		panic(err)
+	}
+	return t
+}

hplot/ticks_test.go

@@ -13,3 +13,7 @@ import (
 func TestTicks(t *testing.T) {
 	checkPlot(cmpimg.CheckPlot)(ExampleTicks, t, "ticks.png")
 }
+
+func TestTicksTime(t *testing.T) {
+	checkPlot(cmpimg.CheckPlot)(ExampleTicks_timeseries, t, "timeseries.png")
+}