ncdfFlow: A package that provides HDF5 based storage for cytometry data.

This package extends the flowCore infrastructure by storing the large volume of event-level data on disk as HDF format and only keeps the file handler and meta data in memory. Thus the memory consumption is significantly reduced.

INSTALLATION

# First, install it from bionconductor so that it will pull all the dependent packages automatically
library(BiocInstalller)
bicLite(ncdfFlow) 

# or install the latest version from github using devtools package 
install.packages("devtools") 
library(devtools) #load it
install_github("RGLab/ncdfFlow", ref="trunk")

Unix/Linux/Mac users

To build the ncdfFlow package from source, make sure that HDF5 Library is present on your system:

If HDF5 is installed to some non-standard location, you may pass the environment variable –with-hdf5 to point to the correct location of HDF5, for example,

#install from github
install_github('RGLab/ncdfFlow', ref='trunk', args='--configure-args="--with-hdf5=<path-to-hdf>"')
 
#or install from locally downloaded tar ball
R CMD INSTALL ncdfFlow_x.y.z.tar.gz --configure-args="--with-hdf5='<path-to-hdf>'"

under ‘/path/to’, you should find “include” and “lib” sub-folders that contain HDF5 headers and shared libraries.

Also, make sure add the path of libhdf5.so (should be lib subfolder of <path-to-hdf>) to your environment variable LD_LIBRARY_PATH so that it can be found at runtime.

export LD_LIBRARY_PATH=<path-to-hdf>/lib:LD_LIBRARY_PATH

Create ncdfFlowSet object

library(ncdfFlow)

#read from FCS files
path <- system.file("extdata","compdata","data",package="flowCore")
files <- list.files(path,full.names=TRUE)[1:3]
fs <- read.ncdfFlowSet(files=files) #equivalent to flowCore::read.flowSet


#or convert the existing flowSet into ncdfFlowSet
data(GvHD)
fs <- GvHD[1:4]
fs <- ncdfFlowSet(fs)
fs

## An ncdfFlowSet with 4 samples.
## NCDF file : /tmp/RtmpENFQmY/ncfs85d52869372e.nc 
## An object of class 'AnnotatedDataFrame'
##   rowNames: s5a01 s5a02 s5a03 s5a04
##   varLabels: Patient Visit ... name (5 total)
##   varMetadata: labelDescription
## 
##   column names:
##     FSC-H, SSC-H, FL1-H, FL2-H, FL3-H, FL2-A, FL4-H, Time

Use it as the same way as flowSet (except it is memory efficient and fast)

pData(fs)

##       Patient Visit Days Grade  name
## s5a01       5     1   -6     3 s5a01
## s5a02       5     2    0     3 s5a02
## s5a03       5     3    6     3 s5a03
## s5a04       5     4   12     3 s5a04

sampleNames(fs)

## [1] "s5a01" "s5a02" "s5a03" "s5a04"

keyword(fs,"FILENAME")

##       FILENAME
## s5a01 "s5a01" 
## s5a02 "s5a02" 
## s5a03 "s5a03" 
## s5a04 "s5a04"

colnames(fs)

## [1] "FSC-H" "SSC-H" "FL1-H" "FL2-H" "FL3-H" "FL2-A" "FL4-H" "Time"

length(fs)

## [1] 4

fs[[1]]

## flowFrame object 's5a01'
## with 3420 cells and 8 observables:
##      name              desc range minRange maxRange
## $P1 FSC-H        FSC-Height  1024        0     1023
## $P2 SSC-H        SSC-Height  1024        0     1023
## $P3 FL1-H         CD15 FITC  1024        1    10000
## $P4 FL2-H           CD45 PE  1024        1    10000
## $P5 FL3-H        CD14 PerCP  1024        1    10000
## $P6 FL2-A              <NA>  1024        0     1023
## $P7 FL4-H          CD33 APC  1024        1    10000
## $P8  Time Time (51.20 sec.)  1024        0     1023
## 153 keywords are stored in the 'description' slot

fs[2:3]

## An ncdfFlowSet with 2 samples.
## NCDF file : /tmp/RtmpENFQmY/ncfs85d52869372e.nc 
## An object of class 'AnnotatedDataFrame'
##   rowNames: s5a02 s5a03
##   varLabels: Patient Visit ... name (5 total)
##   varMetadata: labelDescription
## 
##   column names:
##     FSC-H, SSC-H, FL1-H, FL2-H, FL3-H, FL2-A, FL4-H, Time