Method Draw

plot.go:154–233

(data *DataTable)

}

func (c *LineChart) Draw(data *DataTable) (out string) {
	var scaleY, scaleX float64

	c.data = data

	if c.Flags&DRAW_INDEPENDENT != 0 && len(data.columns) > 3 {
		fmt.Println("Error: Can't use DRAW_INDEPENDENT for more then 2 graphs")
		return ""
	}

	charts := len(data.columns) - 1

	prevPoint := [2]int{-1, -1}

	maxX, minX, maxY, minY := getBoundaryValues(data, -1)

	c.paddingX = int(math.Max(float64(len(ff(minY))), float64(len(ff(maxY))))) + 1

	c.chartHeight = c.Height - c.paddingY

	if c.Flags&DRAW_INDEPENDENT != 0 {
		c.chartWidth = c.Width - 2*c.paddingX
	} else {
		c.chartWidth = c.Width - c.paddingX - 1
	}

	scaleX = float64(c.chartWidth) / (maxX - minX)

	if c.Flags&DRAW_RELATIVE != 0 || minY < 0 {
		scaleY = float64(c.chartHeight) / (maxY - minY)
	} else {
		scaleY = float64(c.chartHeight) / maxY
	}

	for i := 1; i < charts+1; i++ {
		if c.Flags&DRAW_INDEPENDENT != 0 {
			maxX, minX, maxY, minY = getBoundaryValues(data, i)

			scaleX = float64(c.chartWidth-1) / (maxX - minX)
			scaleY = float64(c.chartHeight) / maxY

			if c.Flags&DRAW_RELATIVE != 0 || minY < 0 {
				scaleY = float64(c.chartHeight) / (maxY - minY)
			}
		}

		symbol := Color("•", i)

		c_data := getChartData(data, i)

		for _, point := range c_data {
			x := int((point[0]-minX)*scaleX) + c.paddingX
			y := int((point[1])*scaleY) + c.paddingY

			if c.Flags&DRAW_RELATIVE != 0 || minY < 0 {
				y = int((point[1]-minY)*scaleY) + c.paddingY
			}