How do you change the colors of certain cells in an xtable markdown?

Question

I have a data frame j:

dput(j) structure(list(Trans = c(89.8, 3337, NA, 97.55, NA, 3558.7, NA, 4290.6, NA, 65.95, 94.55, 3495.9), `%CPU` = c(6.938, 79.853, 1.875, 4.87, 1.46, 37.885, 1.63, 64.576, 1.165, 3.425, 5.67, 33.856), `%Heap Used` = c(9.9, 76.95, 3.77, 9.8, 6.73, 59.23, 3.94, 67.38, 3.73, 9.13, 9.57, 62.11), `Heap Usage/MB` = c(263.884, 1942.246, 99.104, 257.717, 178.951, 1657.447, 99.933, 2137.134, 96.687, 242.024, 256.302, 1646.117)), .Names = c("Trans", "%CPU", "%Heap Used", "Heap Usage/MB"), class = "data.frame", row.names = c(NA, -12L)) 

If I want to color the code of a cell based on a threshold in r markdown, how would I do it?

For example, if% CPU> 70, I need to color the code so that the cell is red.

I can print it in r markdown as follows:

 print(xtable(j_cor,digits=2,row.names=FALSE,caption="JVM Usage"),caption.placement="top", tabular.environment="longtable",comment=FALSE,floating=FALSE) 

But I like to place colors in cells based on markdown threshold r Any ideas?

I tried something like this, but the color or cell did not change in the pdf file:

 j[,2] = ifelse(j[,2] < 60, paste0("\\colorbox{red}{", j[,2], "}"), j[,2]) sessionInfo() R version 3.2.4 (2016-03-10) Platform: x86_64-w64-mingw32/x64 (64-bit) Running under: Windows 7 x64 (build 7601) Service Pack 1 locale: [1] LC_COLLATE=English_United States.1252 LC_CTYPE=English_United States.1252 LC_MONETARY=English_United States.1252 [4] LC_NUMERIC=C LC_TIME=English_United States.1252 attached base packages: [1] stats4 grid stats graphics grDevices utils datasets methods base other attached packages: [1] ggthemes_3.4.0 flexclust_1.3-4 modeltools_0.2-21 lattice_0.20-35 tidyr_0.6.1 jsonlite_1.4 Rcpp_0.12.10 lazyeval_0.2.0 [9] knitr_1.16 gridExtra_2.0.0 xtable_1.8-0 data.table_1.9.6 cowplot_0.6.2 reshape2_1.4.1 corrplot_0.77 scales_0.4.1 [17] stringr_1.0.0 chron_2.3-47 ggplot2_2.2.1 dplyr_0.5.0 purrr_0.2.2 xml2_1.0.0 plyr_1.8.4 RCurl_1.95-4.7 [25] bitops_1.0-6 XML_3.98-1.3 httr_1.0.0 rmarkdown_1.5 loaded via a namespace (and not attached): [1] tools_3.2.4 digest_0.6.12 evaluate_0.10 tibble_1.3.0 gtable_0.2.0 DBI_0.6-1 parallel_3.2.4 yaml_2.1.14 [9] rprojroot_1.2 R6_2.2.1 magrittr_1.5 backports_1.1.0 htmltools_0.3.5 assertthat_0.2.0 colorspace_1.3-2 labeling_0.3 [17] stringi_1.1.5 munsell_0.4.3 

I copied the exact text to my Rstudio and tried to run it, I get this error:

 "C:/Program Files/RStudio/bin/pandoc/pandoc" +RTS -K512m -RTS test_color.utf8.md --to latex --from markdown+autolink_bare_uris+ascii_identifiers+tex_math_single_backslash --output test_color.pdf --template "C:\R\win-library\3.2\rmarkdown\rmd\latex\default.tex" --highlight-style tango --latex-engine xelatex --variable graphics=yes --variable "geometry:margin=1in" ! LaTeX Error: Missing \begin{document}. See the LaTeX manual or LaTeX Companion for explanation. Type H <return> for immediate help. ... l.1 < pandoc.exe: Error producing PDF from TeX source Error: pandoc document conversion failed with error 43 In addition: Warning message: running command '"C:/Program Files/RStudio/bin/pandoc/pandoc" +RTS -K512m -RTS test_color.utf8.md --to latex --from markdown+autolink_bare_uris+ascii_identifiers+tex_math_single_backslash --output test_color.pdf --template "C:\Documents\R\win-library\3.2\rmarkdown\rmd\latex\default.tex" --highlight-style tango --latex-engine xelatex --variable graphics=yes --variable "geometry:margin=1in"' had status 43 

Answer 1

Be careful with the % signs in column names. You will need to specify cleanup functions for the text, process LaTeX commands and column names in order to process percent signs.

Use the \cellcolor to color the cell in the LaTeX table.

Here is an example .Rmd file

 --- title: "Colors of xtable cells" header-includes: - \usepackage{longtable} - \usepackage[table]{xcolor} - \usepackage{colortbl} output: pdf_document --- Build the example data set ```{r, include = FALSE} library(xtable) j <- structure(list(Trans = c(89.8, 3337, NA, 97.55, NA, 3558.7, NA, 4290.6, NA, 65.95, 94.55, 3495.9), `%CPU` = c(6.938, 79.853, 1.875, 4.87, 1.46, 37.885, 1.63, 64.576, 1.165, 3.425, 5.67, 33.856), `%Heap Used` = c(9.9, 76.95, 3.77, 9.8, 6.73, 59.23, 3.94, 67.38, 3.73, 9.13, 9.57, 62.11), `Heap Usage/MB` = c(263.884, 1942.246, 99.104, 257.717, 178.951, 1657.447, 99.933, 2137.134, 96.687, 242.024, 256.302, 1646.117)), .Names = c("Trans", "%CPU", "%Heap Used", "Heap Usage/MB"), class = "data.frame", row.names = c(NA, -12L)) ``` Create a version of the `data.frame` with red cells for \%CPU greater than 70. Set the color and round to two digits. ```{r, include = FALSE} j[, 2] <- ifelse(j[, 2] > 70, paste("\\cellcolor{red}{", round(j[, 2], 2), "}"), round(j[, 2], 2)) ``` The resulting table is: ```{r results = "asis"} print(xtable(j, digits = 2, row.names = FALSE, caption = "JVM Usage"), sanitize.text.function = identity, sanitize.colnames.function = NULL, caption.placement = "top", tabular.environment = "longtable", comment = FALSE, floating=FALSE) ``` 

Which produces the following output: