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R Cook Book
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tropf
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My personal recipes when using
.URL "https://r-project.org/" "R" "."
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.NH 1
Intro
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I use R mainly for plotting and some data post-processing.
This document collects some tricks I encountered and use.
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For plotting I use
.URL "https://github.com/tidyverse/ggplot2/" "ggplot2" ","
which ist assumed to exist in these examples.
A variable
.CW "p"
is typically a ggplot2 plot object.
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.NH 1
Hiding Legend, but Preserving its Space
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To hide a legend,
but still take up its space (e.g. to build plots over multiple instances) add the following to the legend.
Adjust the aesthetic used.
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p <- p +
    guides(fill=guide_legend(override.aes=list(fill=NA))) +
    theme(legend.text=element_text(color="#00000000"),
          legend.title=element_text(color="#00000000"))
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.NH 1
aggregate() with more than one output value
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To aggregate with multiple outputs, use the following snippet.
Note that this only works if all outputs have the same type.
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aggrs <- aggregate(to_be_summarized ~ category,
                   df,
                   function(v){c(mean=mean(v), sd=sd(v), min=min(v), max=max(v))})
extra_df <- data.frame(aggrs$to_be_summarized)
aggrs$to_be_summarized <- NULL
colnames(extra_df) <- paste("to_be_summarized", colnames(extra_df), sep=".")
aggrs <- cbind(aggrs, extra_df)
rm(extra_df)
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