func (pp *PlotParams) Defaults() {
	if pp.LineWidth == 0 {
		pp.LineWidth = 1
		pp.Lines = true
		pp.Points = false
		pp.PointSize = 3
		pp.BarWidth = .8
	}
	if pp.Scale == 0 {
		pp.Scale = 2
	}
}
Defaults sets defaults if nil vals present
package eplot
import (
	"github.com/emer/etable/etable"
	"github.com/emer/etable/minmax"
	"github.com/goki/gi/gi"
	"github.com/goki/gi/gist"
	"github.com/goki/ki/kit"
)
type PlotParams struct {
	Title      string    `desc:"optional title at top of plot"`
	Type       PlotTypes `desc:"type of plot to generate.  For a Bar plot, items are plotted ordinally by row and the XAxis is optional"`
	Lines      bool      `desc:"plot lines"`
	Points     bool      `desc:"plot points with symbols"`
	LineWidth  float64   `desc:"width of lines"`
	PointSize  float64   `desc:"size of points"`
	BarWidth   float64   `min:"0.01" max:"1" desc:"width of bars for bar plot, as fraction of available space -- 1 = no gaps, .8 default"`
	NegXDraw   bool      `desc:"draw lines that connect points with a negative X-axis direction -- otherwise these are treated as breaks between repeated series and not drawn"`
	Scale      float64   `def:"2" desc:"overall scaling factor -- the larger the number, the larger the fonts are relative to the graph"`
	XAxisCol   string    `desc:"what column to use for the common X axis -- if empty or not found, the row number is used.  This optional for Bar plots -- if present and LegendCol is also present, then an extra space will be put between X values."`
	XAxisLabel string    `desc:"optional label to use for XAxis instead of column name"`
	YAxisLabel string    `desc:"optional label to use for YAxis -- if empty, first column name is used"`
	XAxisRot   float64   `desc:"rotation of the X Axis labels, in degrees"`
	LegendCol  string    `desc:"optional column for adding a separate colored / styled line or bar according to this value -- acts just like a separate Y variable, crossed with Y variables"`
	Plot       *Plot2D   `copy:"-" json:"-" xml:"-" view:"-" desc:"our plot, for update method"`
}