Nozzle is a report generation toolkit for data analysis pipelines implemented in R.
Switch branches/tags
Clone or download
Pull request Compare This branch is even with parklab:develop.
Fetching latest commit…
Cannot retrieve the latest commit at this time.
Failed to load latest commit information.


Nozzle is an R package that provides an API to generate HTML reports with dynamic user interface elements based on JavaScript and CSS (Cascading Style Sheets). Nozzle was designed to facilitate summarization and rapid browsing of complex results in data analysis pipelines where multiple analyses are performed frequently on big data sets. The package can be applied to any project where user-friendly reports need to be created.

A paper describing the package was published in Bioinformatics. Please cite this paper if you are using Nozzle in your work:

N Gehlenborg, MS Noble, G Getz, L Chin and PJ Park, "Nozzle: a report generation toolkit for data analysis pipelines", Bioinformatics 29:1089-1091 (2013)

A nozzleized version of the preprint is available on the Nozzle site at the Broad Institute and the source code is included in this repository.

About the Name

The package was orignally developed for a data analysis pipeline called "Firehose" and the name "Nozzle" was chosen because the package is used to focus the output of Firehose. The "R1" in the "Nozzle.R1" package name stands for "revision 1" of the Nozzle R API. All versions of the Nozzle.R1 package will be backwards-compatible and able to render reports generated with earlier versions of the package. When backwards-compatibility of the API can no longer maintained the package name will change to "Nozzle.R2".

Obtaining and Installing the R package

As of version 1.0-0 the R package is available from CRAN and can be installed directly from R:

install.packages( "Nozzle.R1", type="source" );

The package can also be downloaded from the Nozzle site at the Broad Institute. The package has no external dependencies and can be installed by calling the following from the command line:

R CMD install Nozzle.R1

Creating a Basic Report

The following code creates a report with one section and two subsections. The first subsection contains a table and the second subsection contains a paragraph of text:

require( Nozzle.R1 )

# Phase 1: create report elements
r <- newCustomReport( "My Report" );
s <- newSection( "My Section" );
ss1 <- newSection( "My Subsection 1" );
ss2 <- newSection( "My Subsection 2" );
f <- newTable( iris[45:55,], "Iris data." ); # w/ caption
p <- newParagraph( "Some sample text." );

# Phase 2: assemble report structure bottom-up
ss1 <- addTo( ss1, f ); # parent, child_1, ..., child_n 
ss2 <- addTo( ss2, p );
s <- addTo( s, ss1, ss2 );
r <- addTo( r, s );

# Phase 3: render report to file
writeReport( r, filename="my_report" ); # w/o extension

Two files called my_report.html and my_report.RData will be written to the current working directory.

Further Examples

An comprehensive demo that uses almost the complete Nozzle API is in the examples folder. Both the demo.R file and the demo.css file are required for the example to work. The rendered HTML reports can be viewed on the Nozzle site at the Broad Institute.

Building the R package

Nozzle works with R 2.10 or later. Use standard R commands to build the package in the cloned repo directory:

R CMD check Nozzle.R1
R CMD build Nozzle.R1

Updating Documentation

The Nozzle API is documented using the roxygen2 R package. To rebuild the Rd files in the man directory run the following from the R shell (using the cloned repo directory as the working directory):

roxygenize("Nozzle.R1", copy=FALSE);

Minifying Files

The JavaScript and CSS code should be compressed before they can be embedded in the HTML report. If you make changes to any file in the inst directory you need to download the [YUI compressor] ( and run the following from the command line:

java -jar Tools/yuicompressor-2.4.2.jar -o Nozzle.R1/inst/js/nozzle.min.js 	Nozzle.R1/inst/js/nozzle.js
java -jar Tools/yuicompressor-2.4.2.jar -o Nozzle.R1/inst/css/nozzle.print.min.css Nozzle.R1/inst/css/nozzle.print.css
java -jar Tools/yuicompressor-2.4.2.jar -o Nozzle.R1/inst/css/nozzle.min.css Nozzle.R1/inst/css/nozzle.css


Nils Gehlenborg ([] (


Nozzle was developed with funding from The Cancer Genome Atlas program of the National Cancer Institute, U24 CA143867.