Either a data frame, a BED file, a .broadPeak file, or a .narrowPeak file. The data frame should have at least 3 columns: chrom, start, and end. Chrom should follow UCSC convention, e.g. "chrX". The file should be tab-delimited.
locusdef
A string denoting the locus definition to be used. A locus definition controls how peaks are assigned to genes. See supported_locusdefs for a list of supported definitions.
genome
A string indicating the genome upon which the peaks file is based. Supported genomes are listed by the supported_genomes function.
use_mappability
If true, each gene's locus length is corrected for by mappability.
read_length
If using mappability (see above), the read length should match the length of reads used in the original experiment.
mappa_file
Path to a file containing user-specified gene locus mappability. The file should contain two columns: geneid and mappa. Gene IDs should be Entrez gene IDs. Mappability values should be between 0 and 1.
Details
The x-axis is gene locus length (for the defined locusdef.) The y-axis is count of peaks. Each blue dot represents the observed count of peaks assigned to a gene.
The black line represents the expected number of peaks given locus length.
Also drawn are the 5 and 95% percentiles of a Poisson distribution for the expected number of peaks, and the 5 and 95% percentiles adjusted for the number of genes (Bonferroni adjustment - e.g. 0.05 / # of genes.)
library(chipenrich.data)
library(chipenrich)
# Expected peak count plot for the E2F4 dataset.
data(peaks_E2F4)
plot_expected_peaks(peaks_E2F4,genome='hg19')
# Create the plot for a different locus definition
# to compare the effect.
plot_expected_peaks(peaks_E2F4,locusdef='nearest_gene',genome='hg19');
# Create the plot, but write the result to a PDF
# instead of displaying it interactively.
pdf("expected_peak_plot.pdf");
p = plot_expected_peaks(peaks_E2F4,genome='hg19');
dev.off();
Results
R version 3.3.1 (2016-06-21) -- "Bug in Your Hair"
Copyright (C) 2016 The R Foundation for Statistical Computing
Platform: x86_64-pc-linux-gnu (64-bit)
R is free software and comes with ABSOLUTELY NO WARRANTY.
You are welcome to redistribute it under certain conditions.
Type 'license()' or 'licence()' for distribution details.
R is a collaborative project with many contributors.
Type 'contributors()' for more information and
'citation()' on how to cite R or R packages in publications.
Type 'demo()' for some demos, 'help()' for on-line help, or
'help.start()' for an HTML browser interface to help.
Type 'q()' to quit R.
> library(chipenrich)
> png(filename="/home/ddbj/snapshot/RGM3/R_BC/result/chipenrich/plot_expected_peaks.Rd_%03d_medium.png", width=480, height=480)
> ### Name: plot_expected_peaks
> ### Title: Plot the expected number of peaks given locus length for each
> ### gene.
> ### Aliases: plot_expected_peaks
>
> ### ** Examples
>
> library(chipenrich.data)
> library(chipenrich)
>
> # Expected peak count plot for the E2F4 dataset.
> data(peaks_E2F4)
> plot_expected_peaks(peaks_E2F4,genome='hg19')
Assigning peaks to genes..
>
> # Create the plot for a different locus definition
> # to compare the effect.
> plot_expected_peaks(peaks_E2F4,locusdef='nearest_gene',genome='hg19');
Assigning peaks to genes..
>
> ## No test:
> # Create the plot, but write the result to a PDF
> # instead of displaying it interactively.
> pdf("expected_peak_plot.pdf");
> p = plot_expected_peaks(peaks_E2F4,genome='hg19');
Assigning peaks to genes..
> dev.off();
png
2
> ## End(No test)
>
>
>
>
>
> dev.off()
null device
1
>