generate.fake.data: Generate simulated ChIP-chip data.

Description Usage Arguments Details Value Author(s) References See Also Examples

Description

Generate simulated ChIP-chip data, as described in Reference (1).

Usage

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generate.fake.data(posns = seq(1, 6001, by = 20), n.pts = 5, noise =
0.1, min.pk = 0.1, plot = F, verbose = F, in.pts = NULL, kernel = NULL,
tile.size = 100, reps = 1,
noise.func = function(data)noise*(1+sqrt(data)), ...)

Arguments

posns

Probe centers

n.pts

Number of (randomly-chosen) binding sites to add

noise

Level of noise (as described in Reference (1))

min.pk

Minimum peak intensity

plot

Plot the generated data?

verbose

Be verbose?

in.pts

2-column matrix with positions (column 1) and intensities (column 2) of input peaks; if n.pts is 'NA'.

kernel

Input peak profile to use.

tile.size

Input probe length (used to generate peak profile kernel if 'kernel' is 'NULL')

noise.func

Function used to generate noise as a function of signal intensity

reps

Number of replicate intensities per simulated probe

...

Further parameters for 'generate.binding.profile' (if 'kernel' is 'NULL')

Details

No details.

Value

A list of class containing the following three elements:

input

A two-column matrix containing positions and intensities of input binding sites

data

A two-column matrix containing positions and intensities of simulated probes, can be passed directly to 'chip.deconv'

kernel

The peak profile kernel used to generate the data (as produced by 'generate.binding.profile')

Author(s)

David J Reiss, Institute for Systems Biology

Maintainer: <dreiss@systemsbiology.org>

References

Reiss, DJ and Facciotti, MT and Baliga, NS. (2007). "Model-based deconvolution of genome-wide DNA binding", Bioinformatics; doi: 10.1093/bioinformatics/btm592.
http://baliga.systemsbiology.net/medichi

See Also

chip.deconv, generate.binding.profile

Examples

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## Generate data with 2 peaks at positions 3000 and 4000, deconvolve the
## data, and plot the resulting data and fit.
kern.300 <- generate.binding.profile( fragment=function(x) dgamma( x,
                     shape=6, scale=50 ), verbose=TRUE )
data <- generate.fake.data( in.pts=cbind( c( 3000, 4000 ), c( 1, 0.7 ) ), reps=3, 
                     kernel=kern.300 )
plot( data$data, pch=20 )
fit <- chip.deconv( data$data, center=NA, wind=NA, kernel=data$kernel,
                    fit.res=30, n.boot=10, verbose=TRUE, boot.sample.opt="case" )
plot( fit, boot="prob.scaled" )
print( fit )

MeDiChI documentation built on May 2, 2019, 5:32 p.m.