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OCplus (version 1.46.0)

DrawContourlines: Draw and label a set of pre-calculated isolines

Description

This function draws and labels isolines computed by contourLines, though the labelling is done very clumsily and with a specialized application in mind.

Usage

DrawContourlines(x, label = FALSE, cex = 0.7, vfont = c("sans serif", "bold"), ...)

Arguments

x
a list of isolines as produced by contourLines.
label
a logical value indicating whether to label the isolines.
cex
size of labels
vfont
a vector font specification for the labels as in contour.
...
extra arguments to lines

Details

This routine is used by Tornadoplot and Volcanoplot to draw and label isolines that were computed via contourLines and afterwards transformed. The problem is that all the nice options that contour has for labelling isolines are not avaiable independently, so this function uses the following crude procedure that kind of works for the intended applications:
  • isoline completely left of zerolabel the leftmost point;
  • isoline completely right of zerolabel the rightmost point;
  • isoline crosses zero horizontallylabel the topmost point.

Hopefully, one of these days someone will come up with a nice general-purpose function for doing all the nifty stuff that contour offers.

See Also

contour, contourLines, Tornadoplot