To install this package, start R and enter (uncommented):
# if (!require("BiocManager", quietly = TRUE))
# install.packages("BiocManager")
#
# BiocManager::install("CytoPipeline")
Note that CytoPipeline imports ggplot2 (>= 3.4.1).
The version requirement is due to a bug in version 3.4.0., affecting
ggplot2::geom_hex()
.
The CytoPipeline
package provides infrastructure to
support the definition, run and standardized visualization of
pre-processing and quality control pipelines for flow cytometry data.
This infrastructure consists of two main S4 classes,
i.e. CytoPipeline
and CytoProcessingStep
, as
well as dedicated wrapper functions around selected third-party package
methods often used to implement these pre-processing steps.
In the following sections, we demonstrate how to create a
CytoPipeline
object implementing a simple pre-processing
pipeline, how to run it and how to retrieve and visualize the results
after each step.
The example dataset that will be used throughout this vignette is derived from a reference public dataset accompanying the OMIP-021 (Optimized Multicolor Immunofluorescence Panel 021) article (Gherardin et al. 2014).
A sub-sample of this public dataset is built-in in the
CytoPipeline
package, as the OMIP021 dataset. See the
MakeOMIP021Samples.R
script for more details on how the
OMIP021
dataset was created. This script is to be found in
the script
subdirectory in the CytoPipeline
package installation path.
Note that in the CytoPipeline
package, as in the current
vignette, matrices of flow cytometry events intensities are stored as
flowCore::flowFrame
objects (Ellis B
2022).
Let’s assume that we want to pre-process the two samples of the
OMIP021
dataset, and let’s assume that we want to compare
what we would obtain when pre-processing these files using two different
QC methods.
In the first pre-processing pipeline, we will use the flowAI QC method (Monaco et al. 2016), while in the second pipeline, we will use the PeacoQC method (Emmaneel et al. 2021). Note that when we here refer to QC method, we mean the algorithm used to ensure stability (stationarity) of the channel signals in time.
In both pipelines, the first part consists in estimating appropriate
scale transformation functions for all channels present in the sample
flowFrame
. In order to do this, we propose the following
scale transformation processing queue (Fig. 1):
.fcs
filesWhen this first part is done, one can apply pre-processing for each file one by one. However, depending on the choice of QC method, the order of steps needs to be slightly different:
Therefore, we propose the following pre-processing queues represented in Fig. 2.
CytoPipeline
is the central S4 class used in the
CytoPipeline
package to represent a flow cytometry
pre-processing pipeline. The main slots of CytoPipeline
objects are :
an experimentName
, which gives a name to a
particular user definition of a pre-processing pipeline. The
experiment here, is not related to an assay experiment, but
refers to a specific way to design a pipeline. For example, in the
current use case, we will define two experimentName
s, one
to refer to the flowAI pipeline, and another one to refer to the PeacoQC
pipeline (see previous section);
a vector of sampleFiles
, which are .fcs
raw data files on which one need to run the pre-processing
pipeline;
two processing queues, i.e. a
scaleTransformProcessingQueue
, and a
flowFramesPreProcessingQueue
, which correspond to the two
parts described in previous section. Each of these queues are composed
of one or several CytoProcessingStep
objects, will be
processed in linear sequence, the output of one step being the input of
the next step.
Note there are important differences between the two processing
queues. On the one hand, the scaleTransformProcessingQueue
takes the vector of all sample files as an input, and will be executed
first, and only once. On the other hand, the
flowFramesPreProcessingQueue
will be run after the scale
transformation processing queue, on each sample file one after the
other, within a loop. The final output of the
scaleTransformProcessingQueue
, which should be a
flowCore::tranformList
, is also provided as input to the
flowFramesPreProcessingQueue
, by convention.
In the next subsections, we show the different steps involved in
creating a CytoPipeline
object.
In the following code, rawDataDir
refers to the
directory in which the .fcs
raw data files are stored.
workDir
will be used as root directory to store the disk
cache. Indeed, when running the CytoPipeline
objects, all
the different step outputs will be stored in a
BiocFileCache
instance, in a sub-directory that will be
created in workDir
and of which the name will be set to the
pipeline experimentName
.
## Warning: multiple methods tables found for 'setequal'
In this sub-section, we build a CytoPipeline
object and
successively add CytoProcessingStep
objects to the two
different processing queues. We do this for the PeacoQC pipeline.
# main parameters : sample files and output files
experimentName <- "OMIP021_PeacoQC"
sampleFiles <- file.path(rawDataDir, list.files(rawDataDir,
pattern = "Donor"))
pipL_PeacoQC <- CytoPipeline(experimentName = experimentName,
sampleFiles = sampleFiles)
### SCALE TRANSFORMATION STEPS ###
pipL_PeacoQC <-
addProcessingStep(pipL_PeacoQC,
whichQueue = "scale transform",
CytoProcessingStep(
name = "flowframe_read",
FUN = "readSampleFiles",
ARGS = list(
whichSamples = "all",
truncate_max_range = FALSE,
min.limit = NULL
)
)
)
pipL_PeacoQC <-
addProcessingStep(pipL_PeacoQC,
whichQueue = "scale transform",
CytoProcessingStep(
name = "remove_margins",
FUN = "removeMarginsPeacoQC",
ARGS = list()
)
)
pipL_PeacoQC <-
addProcessingStep(pipL_PeacoQC,
whichQueue = "scale transform",
CytoProcessingStep(
name = "compensate",
FUN = "compensateFromMatrix",
ARGS = list(matrixSource = "fcs")
)
)
pipL_PeacoQC <-
addProcessingStep(pipL_PeacoQC,
whichQueue = "scale transform",
CytoProcessingStep(
name = "flowframe_aggregate",
FUN = "aggregateAndSample",
ARGS = list(
nTotalEvents = 10000,
seed = 0
)
)
)
pipL_PeacoQC <-
addProcessingStep(pipL_PeacoQC,
whichQueue = "scale transform",
CytoProcessingStep(
name = "scale_transform_estimate",
FUN = "estimateScaleTransforms",
ARGS = list(
fluoMethod = "estimateLogicle",
scatterMethod = "linear",
scatterRefMarker = "BV785 - CD3"
)
)
)
### FLOW FRAME PRE-PROCESSING STEPS ###
pipL_PeacoQC <-
addProcessingStep(pipL_PeacoQC,
whichQueue = "pre-processing",
CytoProcessingStep(
name = "flowframe_read",
FUN = "readSampleFiles",
ARGS = list(
truncate_max_range = FALSE,
min.limit = NULL
)
)
)
pipL_PeacoQC <-
addProcessingStep(pipL_PeacoQC,
whichQueue = "pre-processing",
CytoProcessingStep(
name = "remove_margins",
FUN = "removeMarginsPeacoQC",
ARGS = list()
)
)
pipL_PeacoQC <-
addProcessingStep(pipL_PeacoQC,
whichQueue = "pre-processing",
CytoProcessingStep(
name = "compensate",
FUN = "compensateFromMatrix",
ARGS = list(matrixSource = "fcs")
)
)
pipL_PeacoQC <-
addProcessingStep(
pipL_PeacoQC,
whichQueue = "pre-processing",
CytoProcessingStep(
name = "perform_QC",
FUN = "qualityControlPeacoQC",
ARGS = list(
preTransform = TRUE,
min_cells = 150, # default
max_bins = 500, # default
step = 500, # default,
MAD = 6, # default
IT_limit = 0.55, # default
force_IT = 150, # default
peak_removal = 0.3333, # default
min_nr_bins_peakdetection = 10 # default
)
)
)
pipL_PeacoQC <-
addProcessingStep(
pipL_PeacoQC,
whichQueue = "pre-processing",
CytoProcessingStep(
name = "remove_doublets",
FUN = "removeDoubletsCytoPipeline",
ARGS = list(
areaChannels = c("FSC-A", "SSC-A"),
heightChannels = c("FSC-H", "SSC-H"),
nmads = c(3, 5))
)
)
pipL_PeacoQC <-
addProcessingStep(pipL_PeacoQC,
whichQueue = "pre-processing",
CytoProcessingStep(
name = "remove_debris",
FUN = "removeDebrisManualGate",
ARGS = list(
FSCChannel = "FSC-A",
SSCChannel = "SSC-A",
gateData = c(73615, 110174, 213000, 201000, 126000,
47679, 260500, 260500, 113000, 35000)
)
)
)
pipL_PeacoQC <-
addProcessingStep(pipL_PeacoQC,
whichQueue = "pre-processing",
CytoProcessingStep(
name = "remove_dead_cells",
FUN = "removeDeadCellsManualGate",
ARGS = list(
FSCChannel = "FSC-A",
LDMarker = "L/D Aqua - Viability",
gateData = c(0, 0, 250000, 250000,
0, 650, 650, 0)
)
)
)
In this sub-section, we build the flowAI pipeline, this time using a
JSON file as an input. Note that the experimentName
and
sampleFiles
are here specified in the JSON file itself.
This is not necessary, as one could well specify the processing steps
only in the JSON file, and pass the experimentName
and
sampleFiles
directly in the CytoPipeline
constructor.
Note: executing the next statement might generate some
warnings.
These are generated by the PeacoQC method
, are highly
dependent on the shape of the data investigated, and can safely be
ignored here.
## #####################################################
## ### running SCALE TRANSFORMATION processing steps ###
## #####################################################
## Proceeding with step 1 [flowframe_read] ...
## Proceeding with step 2 [remove_margins] ...
## Removing margins from file : Donor1.fcs
## Warning: replacing previous import 'BiocGenerics::setequal' by
## 'S4Vectors::setequal' when loading 'IRanges'
## Warning in PeacoQC::RemoveMargins(ff, channels = channel4Margins,
## channel_specifications = PQCChannelSpecs): More than 10.12 % is considered as a
## margin event in file Donor1.fcs . This should be verified.
## Removing margins from file : Donor2.fcs
## Proceeding with step 3 [compensate] ...
## Proceeding with step 4 [flowframe_aggregate] ...
## Proceeding with step 5 [scale_transform_estimate] ...
## #####################################################
## ### NOW PRE-PROCESSING FILE /tmp/RtmpyYtRYX/Rinst1cbc1f258666/CytoPipeline/extdata/Donor1.fcs...
## #####################################################
## Proceeding with step 1 [flowframe_read] ...
## Proceeding with step 2 [remove_margins] ...
## Removing margins from file : Donor1.fcs
## Warning in PeacoQC::RemoveMargins(ff, channels = channel4Margins,
## channel_specifications = PQCChannelSpecs): More than 10.12 % is considered as a
## margin event in file Donor1.fcs . This should be verified.
## Proceeding with step 3 [compensate] ...
## Proceeding with step 4 [perform_QC] ...
## Applying PeacoQC method...
## Starting quality control analysis for Donor1.fcs
## Warning in FindIncreasingDecreasingChannels(breaks, ff, channels, plot, : There
## seems to be an increasing or decreasing trend in a channel for Donor1.fcs .
## Please inspect this in the overview figure.
## Calculating peaks
## Warning in PeacoQC::PeacoQC(ff = ffIn, channels = channel4QualityControl, :
## There are not enough bins for a robust isolation tree analysis.
## MAD analysis removed 38.81% of the measurements
## The algorithm removed 38.81% of the measurements
## Proceeding with step 5 [remove_doublets] ...
## Proceeding with step 6 [remove_debris] ...
## Proceeding with step 7 [remove_dead_cells] ...
## #####################################################
## ### NOW PRE-PROCESSING FILE /tmp/RtmpyYtRYX/Rinst1cbc1f258666/CytoPipeline/extdata/Donor2.fcs...
## #####################################################
## Proceeding with step 1 [flowframe_read] ...
## Proceeding with step 2 [remove_margins] ...
## Removing margins from file : Donor2.fcs
## Proceeding with step 3 [compensate] ...
## Proceeding with step 4 [perform_QC] ...
## Applying PeacoQC method...
## Starting quality control analysis for Donor2.fcs
## Warning in FindIncreasingDecreasingChannels(breaks, ff, channels, plot, : There
## seems to be an increasing or decreasing trend in a channel for Donor2.fcs .
## Please inspect this in the overview figure.
## Calculating peaks
## Warning in PeacoQC::PeacoQC(ff = ffIn, channels = channel4QualityControl, :
## There are not enough bins for a robust isolation tree analysis.
## MAD analysis removed 9.57% of the measurements
## The algorithm removed 9.57% of the measurements
## Proceeding with step 5 [remove_doublets] ...
## Proceeding with step 6 [remove_debris] ...
## Proceeding with step 7 [remove_dead_cells] ...
Note: again this might generate some warnings, due to flowAI.
These are highly dependent on the shape of the data investigated, and
can safely be ignored here.
## #####################################################
## ### running SCALE TRANSFORMATION processing steps ###
## #####################################################
## Proceeding with step 1 [flowframe_read] ...
## Proceeding with step 2 [remove_margins] ...
## Removing margins from file : Donor1.fcs
## Warning in PeacoQC::RemoveMargins(ff, channels = channel4Margins,
## channel_specifications = PQCChannelSpecs): More than 10.12 % is considered as a
## margin event in file Donor1.fcs . This should be verified.
## Removing margins from file : Donor2.fcs
## Proceeding with step 3 [compensate] ...
## Proceeding with step 4 [flowframe_aggregate] ...
## Proceeding with step 5 [scale_transform_estimate] ...
## #####################################################
## ### NOW PRE-PROCESSING FILE /tmp/RtmpyYtRYX/Rinst1cbc1f258666/CytoPipeline/extdata/Donor1.fcs...
## #####################################################
## Proceeding with step 1 [flowframe_read] ...
## Proceeding with step 2 [perform_QC] ...
## Applying flowAI method...
## Quality control for the file: Donor1
## 5.46% of anomalous cells detected in the flow rate check.
## 0% of anomalous cells detected in signal acquisition check.
## 0.12% of anomalous cells detected in the dynamic range check.
## Proceeding with step 3 [compensate] ...
## Proceeding with step 4 [remove_doublets] ...
## Proceeding with step 5 [remove_debris] ...
## Proceeding with step 6 [remove_dead_cells] ...
## #####################################################
## ### NOW PRE-PROCESSING FILE /tmp/RtmpyYtRYX/Rinst1cbc1f258666/CytoPipeline/extdata/Donor2.fcs...
## #####################################################
## Proceeding with step 1 [flowframe_read] ...
## Proceeding with step 2 [perform_QC] ...
## Applying flowAI method...
## Quality control for the file: Donor2
## 66.42% of anomalous cells detected in the flow rate check.
## 0% of anomalous cells detected in signal acquisition check.
## 0.1% of anomalous cells detected in the dynamic range check.
## Proceeding with step 3 [compensate] ...
## Proceeding with step 4 [remove_doublets] ...
## Proceeding with step 5 [remove_debris] ...
## Proceeding with step 6 [remove_dead_cells] ...
# plot work flow graph - PeacoQC - scale transformList
plotCytoPipelineProcessingQueue(
pipL_PeacoQC,
whichQueue = "scale transform",
path = workDir)
# plot work flow graph - PeacoQC - pre-processing
plotCytoPipelineProcessingQueue(
pipL_PeacoQC,
whichQueue = "pre-processing",
sampleFile = 1,
path = workDir)
# plot work flow graph - flowAI - scale transformList
plotCytoPipelineProcessingQueue(
pipL_flowAI,
whichQueue = "scale transform",
path = workDir)
# plot work flow graph - flowAI - pre-processing
plotCytoPipelineProcessingQueue(
pipL_flowAI,
whichQueue = "pre-processing",
sampleFile = 1,
path = workDir)
## ObjectName ObjectClass
## 1 flowframe_read_obj flowSet
## 2 remove_margins_obj flowSet
## 3 compensate_obj flowSet
## 4 flowframe_aggregate_obj flowFrame
## 5 scale_transform_estimate_obj transformList
getCytoPipelineObjectInfos(pipL_PeacoQC,
path = workDir,
whichQueue = "pre-processing",
sampleFile = sampleFiles(pipL_PeacoQC)[1])
## ObjectName ObjectClass
## 1 flowframe_read_obj flowFrame
## 2 remove_margins_obj flowFrame
## 3 compensate_obj flowFrame
## 4 perform_QC_obj flowFrame
## 5 remove_doublets_obj flowFrame
## 6 remove_debris_obj flowFrame
## 7 remove_dead_cells_obj flowFrame
# example of retrieving a flow frame
# at a given step
ff <- getCytoPipelineFlowFrame(
pipL_PeacoQC,
whichQueue = "pre-processing",
sampleFile = 1,
objectName = "remove_doublets_obj",
path = workDir)
#
ff2 <- getCytoPipelineFlowFrame(
pipL_PeacoQC,
whichQueue = "pre-processing",
sampleFile = 1,
objectName = "remove_debris_obj",
path = workDir)
We now provide an example on how to retrieve an object from the
cache, that is not specifically a flowCore::flowFrame
.
Here we retrieve a flowCore::flowSet
object, which
represents a set of
flowCore::flowFrame
objects, that was obtained after the
compensation step of the scale transformation processing queue, prior to
aggregating the two samples.
obj <- getCytoPipelineObjectFromCache(pipL_PeacoQC,
path = workDir,
whichQueue = "scale transform",
objectName = "compensate_obj")
show(obj)
## A flowSet with 2 experiments.
##
## column names(22): FSC-A FSC-H ... Time Original_ID
Getting the number of retained events at each pre-processing step, and tracking these changes throughout the pre-processing steps of a pipeline for different samples is a useful quality control.
This can be implemented using CytoPipeline
collectNbOfRetainedEvents()
function. Examples of using
this function in quality control plots are shown in this section.
ret <- CytoPipeline::collectNbOfRetainedEvents(
experimentName = "OMIP021_PeacoQC",
path = workDir
)
ret
## flowframe_read remove_margins compensate perform_QC remove_doublets
## Donor1.fcs 5000 4494 4494 2750 2189
## Donor2.fcs 5000 4700 4700 4250 3431
## remove_debris remove_dead_cells
## Donor1.fcs 1850 1784
## Donor2.fcs 3019 2984
retainedProp <-
as.data.frame(t(apply(
ret,
MARGIN = 1,
FUN = function(line) {
if (length(line) == 0 || is.na(line[1])) {
as.numeric(rep(NA, length(line)))
} else {
round(line/line[1], 3)
}
}
)))
retainedProp <- retainedProp[-1]
retainedProp
## remove_margins compensate perform_QC remove_doublets remove_debris
## Donor1.fcs 0.899 0.899 0.55 0.438 0.370
## Donor2.fcs 0.940 0.940 0.85 0.686 0.604
## remove_dead_cells
## Donor1.fcs 0.357
## Donor2.fcs 0.597
stepRemovedProp <-
as.data.frame(t(apply(
ret,
MARGIN = 1,
FUN = function(line) {
if (length(line) == 0) {
as.numeric(rep(NA, length(line)))
} else {
round(1-line/dplyr::lag(line), 3)
}
}
)))
stepRemovedProp <- stepRemovedProp[-1]
stepRemovedProp
## remove_margins compensate perform_QC remove_doublets remove_debris
## Donor1.fcs 0.101 0 0.388 0.204 0.155
## Donor2.fcs 0.060 0 0.096 0.193 0.120
## remove_dead_cells
## Donor1.fcs 0.036
## Donor2.fcs 0.012
myGGPlot <- function(DF, title){
stepNames = colnames(DF)
rowNames = rownames(DF)
DFLongFmt <- reshape(DF,
direction = "long",
v.names = "proportion",
varying = stepNames,
timevar = "step",
time = stepNames,
ids = rowNames)
DFLongFmt$step <- factor(DFLongFmt$step, levels = stepNames)
ggplot(data = DFLongFmt,
mapping = aes(x = step, y = proportion, text = id)) +
geom_point(col = "blue") +
ggtitle(title) +
theme(axis.text.x = element_text(angle = 90))
}
p1 <- myGGPlot(DF = retainedProp,
title = "Retained event proportion at each step")
p1
Using the CytoPipelineGUI
package, it is possible to
interactively inspect results at the different steps of the pipeline,
either in the form of flowCore::flowFrame
objects, or
flowCore::transformList
. To do this, install the
CytoPipelineGUI
package, and uncomment the following
code:
As was described in the previous sections, CytoPipeline
requires the user to provide wrappers to pre-processing functions, as
FUN
parameter of CytoProcessingSteps
. These
can be coded by the user themself, or come from a built-in function
provided in CytoPipeline
itself.
However, in order to avoid having too many external dependencies for
CytoPipeline
, another package
CytoPipelineUtils
, is also available
CytoPipelineUtils
is meant to be used in conjunction with
CytoPipeline
package. It is a helper package, which is
aimed at hosting wrapper implementations of various functions of various
packages.
CytoPipelineUtils
is open to contributions. If you want
to implement your own wrapper of your favourite pre-processing function
and use it in a CytoPipeline
object, this is the place to
do it!
## R version 4.4.2 (2024-10-31)
## Platform: x86_64-pc-linux-gnu
## Running under: Ubuntu 24.04.1 LTS
##
## Matrix products: default
## BLAS: /usr/lib/x86_64-linux-gnu/openblas-pthread/libblas.so.3
## LAPACK: /usr/lib/x86_64-linux-gnu/openblas-pthread/libopenblasp-r0.3.26.so; LAPACK version 3.12.0
##
## locale:
## [1] LC_CTYPE=en_US.UTF-8 LC_NUMERIC=C
## [3] LC_TIME=en_US.UTF-8 LC_COLLATE=C
## [5] LC_MONETARY=en_US.UTF-8 LC_MESSAGES=en_US.UTF-8
## [7] LC_PAPER=en_US.UTF-8 LC_NAME=C
## [9] LC_ADDRESS=C LC_TELEPHONE=C
## [11] LC_MEASUREMENT=en_US.UTF-8 LC_IDENTIFICATION=C
##
## time zone: Etc/UTC
## tzcode source: system (glibc)
##
## attached base packages:
## [1] stats graphics grDevices utils datasets methods base
##
## other attached packages:
## [1] ggplot2_3.5.1 reshape2_1.4.4 CytoPipeline_1.7.1 BiocStyle_2.35.0
##
## loaded via a namespace (and not attached):
## [1] changepoint_2.3 tidyselect_1.2.1 farver_2.1.2
## [4] dplyr_1.1.4 blob_1.2.4 filelock_1.0.3
## [7] fastmap_1.2.0 BiocFileCache_2.15.0 XML_3.99-0.17
## [10] digest_0.6.37 lifecycle_1.0.4 cluster_2.1.6
## [13] RSQLite_2.3.7 magrittr_2.0.3 compiler_4.4.2
## [16] rlang_1.1.4 sass_0.4.9 tools_4.4.2
## [19] utf8_1.2.4 yaml_2.3.10 data.table_1.16.2
## [22] knitr_1.48 labeling_0.4.3 bit_4.5.0
## [25] curl_5.2.3 diagram_1.6.5 plyr_1.8.9
## [28] RColorBrewer_1.1-3 withr_3.0.2 purrr_1.0.2
## [31] RProtoBufLib_2.19.0 BiocGenerics_0.53.1 sys_3.4.3
## [34] PeacoQC_1.17.0 grid_4.4.2 stats4_4.4.2
## [37] fansi_1.0.6 flowAI_1.37.0 colorspace_2.1-1
## [40] scales_1.3.0 iterators_1.0.14 cli_3.6.3
## [43] rmarkdown_2.28 crayon_1.5.3 ncdfFlow_2.53.0
## [46] generics_0.1.3 httr_1.4.7 rjson_0.2.23
## [49] DBI_1.2.3 cachem_1.1.0 flowCore_2.19.0
## [52] stringr_1.5.1 zlibbioc_1.52.0 parallel_4.4.2
## [55] BiocManager_1.30.25 matrixStats_1.4.1 vctrs_0.6.5
## [58] jsonlite_1.8.9 cytolib_2.19.0 IRanges_2.41.0
## [61] GetoptLong_1.0.5 S4Vectors_0.45.0 bit64_4.5.2
## [64] clue_0.3-65 Rgraphviz_2.51.0 maketools_1.3.1
## [67] foreach_1.5.2 jquerylib_0.1.4 hexbin_1.28.4
## [70] glue_1.8.0 codetools_0.2-20 stringi_1.8.4
## [73] shape_1.4.6.1 gtable_0.3.6 ggcyto_1.35.0
## [76] ComplexHeatmap_2.23.0 munsell_0.5.1 tibble_3.2.1
## [79] pillar_1.9.0 htmltools_0.5.8.1 graph_1.85.0
## [82] circlize_0.4.16 R6_2.5.1 dbplyr_2.5.0
## [85] doParallel_1.0.17 evaluate_1.0.1 flowWorkspace_4.19.0
## [88] lattice_0.22-6 Biobase_2.67.0 highr_0.11
## [91] png_0.1-8 memoise_2.0.1 bslib_0.8.0
## [94] Rcpp_1.0.13-1 gridExtra_2.3 xfun_0.49
## [97] zoo_1.8-12 buildtools_1.0.0 pkgconfig_2.0.3
## [100] GlobalOptions_0.1.2