// updateChart inserts a dataset into a line chart, scaling appropriately as to
// not display weird labels, also updating the chart label accordingly.
func updateChart(metric string, data []float64, base *int, chart *termui.LineChart, err error) (realign bool) {
dataUnits := []string{"", "K", "M", "G", "T", "E"}
timeUnits := []string{"ns", "µs", "ms", "s", "ks", "ms"}
colors := []termui.Attribute{termui.ColorBlue, termui.ColorCyan, termui.ColorGreen, termui.ColorYellow, termui.ColorRed, termui.ColorRed}
// Extract only part of the data that's actually visible
if chart.Width*2 < len(data) {
data = data[:chart.Width*2]
}
// Find the maximum value and scale under 1K
high := 0.0
if len(data) > 0 {
high = data[0]
for _, value := range data[1:] {
high = math.Max(high, value)
}
}
unit, scale := 0, 1.0
for high >= 1000 && unit+1 < len(dataUnits) {
high, unit, scale = high/1000, unit+1, scale*1000
}
// If the unit changes, re-create the chart (hack to set max height...)
if unit != *base {
realign, *base, *chart = true, unit, *createChart(chart.Height)
}
// Update the chart's data points with the scaled values
if cap(chart.Data) < len(data) {
chart.Data = make([]float64, len(data))
}
chart.Data = chart.Data[:len(data)]
for i, value := range data {
chart.Data[i] = value / scale
}
// Update the chart's label with the scale units
units := dataUnits
if strings.Contains(metric, "/Percentiles/") || strings.Contains(metric, "/pauses/") || strings.Contains(metric, "/time/") {
units = timeUnits
}
chart.Border.Label = metric
if len(units[unit]) > 0 {
chart.Border.Label += " [" + units[unit] + "]"
}
chart.LineColor = colors[unit] | termui.AttrBold
if err != nil {
chart.LineColor = termui.ColorRed | termui.AttrBold
}
return
}
func UpdateGenericChart(l *ui.LineChart, updateFunc func() float64) {
data := make([]float64, 150)
for {
for i := len(data) - 1; i > 0; i-- {
data[i] = data[i-1]
}
data[0] = updateFunc()
l.Data = data
time.Sleep(500 * time.Millisecond)
}
}