trendTicks {GCDkit}R Documentation

Petrogenetic trends

Description

Adding a trend with arrow and tick marks to a pre-existing GCDkit plot.

Usage

trendTicks(equation, x, xmin = par("usr")[1], xmax = par("usr")[2], 
    text = FALSE, col = "blue", lty = "solid", lwd = 1, arrow = FALSE, 
    autoscale = TRUE)

Arguments

equation

character or expression; a valid formula expressed as a function of x.

x

numeric; x values where the ticks are to be drawn.

xmin

numeric; beginning of the trend.

xmax

numeric; end of the trend.

text

logical; should be the tick marks annotated by text?

col

text or numeric; plotting colour specification.

lty

text or numeric; the line type.

lwd

numeric; the line width, a positive number, defaulting to 1.

arrow

logical; should be also an arrow head shown?

autoscale

logical; should the plot be autosized in order to accommodate the whole trend as well as all data points?

Details

Using the function curve, the function trendTicks adds to an existing GCDkit plot a linear or curved trend with tick marks and (optionally) arrow head. It is required that the trend is defined as a function of x. The slope of the individual tick marks is then determined using a derivation of the main function at the respective points.

trendTicks.png

Value

a list with two components, x and y, with coordinates of the tick marks.

Warning

Autoscaling will work only with Figaro compatible plots!

Author(s)

Vojtech Janousek, vojtech.janousek@geology.cz

See Also

par

Examples

    binary("Ba","Sr",xmin=200,xmax=2000,ymin=10,ymax=400)
    equation<-"x/8+200"
    x<-seq(2000,500,by=-100)
    trendTicks(equation,x,min(x),max(x),col="darkred",lty="solid",lwd=2,arrow=T,text=F)
    
    plot(1,1,type="n",xlim=c(0.01,1),ylim=c(0,1),xlab="Rb",ylab="Sr",log="x")
    equation<-"6*x/8"
    x<-seq(0.01,1,by=0.1)
    trendTicks(equation,x,min(x),max(x),col=2,lwd=2,arrow=F,text=F,autoscale=F)

[Package GCDkit version 4.1 Index]