phangorn (version 2.11.1)

simSeq: Simulate sequences.

Description

Simulate sequences from a given evolutionary tree.

Usage

simSeq(x, ...)
# S3 method for phylo
simSeq(x, l = 1000, Q = NULL, bf = NULL,
  rootseq = NULL, type = "DNA", model = NULL, levels = NULL,
  rate = 1, ancestral = FALSE, code = 1, ...)
# S3 method for pml
simSeq(x, ancestral = FALSE, ...)

Value

simSeq returns an object of class phyDat.

Arguments

x

a phylogenetic tree tree, i.e. an object of class phylo or and object of class pml.

...

Further arguments passed to or from other methods.

l

The length of the sequence to simulate.

Q

The rate matrix.

bf

Base frequencies.

rootseq

A vector of length l containing the root sequence. If not provided, the root sequence is randomly generated.

type

Type of sequences ("DNA", "AA", "CODON" or "USER").

model

Amino acid model of evolution to employ, for example "WAG", "JTT", "Dayhoff" or "LG". For a full list of supported models, type phangorn:::.aamodels. Ignored if type is not equal to "AA".

levels

A character vector of the different character tokens. Ignored unless type = "USER".

rate

A numerical value greater than zero giving the mutation rate or scaler for edge lengths.

ancestral

Logical specifying whether to return ancestral sequences.

code

The ncbi genetic code number for translation (see details). By default the standard genetic code is used.

Author

Klaus Schliep

Details

simSeq is a generic function to simulate sequence alignments along a phylogeny. It is quite flexible and can generate DNA, RNA, amino acids, codon, morphological or binary sequences. simSeq can take as input a phylogenetic tree of class phylo, or a pml object; it will return an object of class phyDat. There is also a more low level version, which lacks rate variation, but one can combine different alignments with their own rates (see example). The rate parameter acts like a scaler for the edge lengths.

For codon models type="CODON", two additional arguments dnds for the dN/dS ratio and tstv for the transition transversion ratio can be supplied.

Defaults:

If x is a tree of class phylo, then sequences will be generated with the default Jukes-Cantor DNA model ("JC").

If bf is not specified, then all states will be treated as equally probable.

If Q is not specified, then a uniform rate matrix will be employed.

See Also

phyDat, pml, SOWH.test

Examples

if (FALSE) {
data(Laurasiatherian)
tree <- nj(dist.ml(Laurasiatherian))
fit <- pml(tree, Laurasiatherian, k=4)
fit <- optim.pml(fit, optNni=TRUE, model="GTR", optGamma=TRUE)
data <- simSeq(fit)
}


tree <- rtree(5)
plot(tree)
nodelabels()

# Example for simple DNA alignment
data <- simSeq(tree, l = 10, type="DNA", bf=c(.1,.2,.3,.4), Q=1:6,
               ancestral=TRUE)
as.character(data)


# Example to simulate discrete Gamma rate variation
rates <- discrete.gamma(1,4)
data1 <- simSeq(tree, l = 100, type="AA", model="WAG", rate=rates[1])
data2 <- simSeq(tree, l = 100, type="AA", model="WAG", rate=rates[2])
data3 <- simSeq(tree, l = 100, type="AA", model="WAG", rate=rates[3])
data4 <- simSeq(tree, l = 100, type="AA", model="WAG", rate=rates[4])
data <- c(data1,data2, data3, data4)

write.phyDat(data, file="temp.dat", format="sequential", nbcol = -1,
  colsep = "")
unlink("temp.dat")