(This article was first published on SAS and R, and kindly contributed to R-bloggers)
A contour plot is a simple way to plot a surface in two dimensions. Lines with a constant Z value are plotted on the X-Y plane.Typical uses include weather maps displaying "isobars" (lines of constant pressure), and maps displaying lines of constant elevation useful in, e.g., hiking. Unusual examples include maps of constant travel time, for example this map, which transforms space so that To leave a comment for the author, please follow the link and comment on his blog: SAS and R.
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Zero Inflated Models and Generalized Linear Mixed Models with R.
Zuur, Saveliev, Ieno (2012).
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Example 7.31: Contour plot of BMI by weight and height [link to post]
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