view_motifs: Plot motif logos.

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

View source: R/view_motifs.R

Description

Show sequence logo. If given a list of more than one motif, then the motifs are aligned with the first in the list.

Usage

1
2
3
4
5
view_motifs(motifs, use.type = "ICM", method = "ALLR", tryRC = TRUE,
  min.overlap = 6, min.mean.ic = 0.25, relative_entropy = FALSE,
  normalise.scores = FALSE, min.position.ic = 0, score.strat = "sum",
  return.raw = FALSE, dedup.names = FALSE, show.positions = TRUE,
  show.positions.once = TRUE, show.names = TRUE, ...)

Arguments

motifs

See convert_motifs() for acceptable motif formats.

use.type

character(1) One of c('PCM', 'PPM', 'PWM', 'ICM').

method

character(1) One of PCC, EUCL, SW, KL, ALLR, BHAT, HELL, SEUCL, MAN, ALLR_LL, WEUCL, WPCC. See details.

tryRC

logical(1) Try the reverse complement of the motifs as well, report the best score.

min.overlap

numeric(1) Minimum overlap required when aligning the motifs. Setting this to a number higher then the width of the motifs will not allow any overhangs. Can also be a number between 0 and 1, representing the minimum fraction that the motifs must overlap.

min.mean.ic

numeric(1) Minimum mean information content between the two motifs for an alignment to be scored. This helps prevent scoring alignments between low information content regions of two motifs.

relative_entropy

logical(1) Change the ICM calculation affecting min.position.ic and min.mean.ic. See convert_type().

normalise.scores

logical(1) Favour alignments which leave fewer unaligned positions, as well as alignments between motifs of similar length. Similarity scores are multiplied by the ratio of aligned positions to the total number of positions in the larger motif, and the inverse for distance scores.

min.position.ic

numeric(1) Minimum information content required between individual alignment positions for it to be counted in the final alignment score. It is recommended to use this together with normalise.scores = TRUE, as this will help punish scores resulting from only a fraction of an alignment.

score.strat

character(1) How to handle column scores calculated from motif alignments. "sum": add up all scores. "a.mean": take the arithmetic mean. "g.mean": take the geometric mean. "median": take the median. "wa.mean", "wg.mean": weighted arithmetic/geometric mean. "fzt": Fisher Z-transform. Weights are the total information content shared between aligned columns.

return.raw

logical(1) Instead of returning a plot, return the aligned named matrices used to generate the plot. This can be useful if you wish to use view_motifs() alignment capabilities for custom plotting uses. Alignment is performed by adding empty columns to the left or right of motifs to generate matrices of equal length.

dedup.names

logical(1) Plotting motifs with duplicated names is not allowed. Setting this to TRUE allows the names to be modified for plotting.

show.positions

logical(1) Show x-axis position tick labels.

show.positions.once

logical(1) When plotting multiple motifs, show x-axis position tick labels only once.

show.names

logical(1) Add motif names when plotting multiple motifs.

...

Additional options for ggseqlogo::geom_logo().

Details

Since the ggseqlogo package can only plot individual characters and not strings, plotting the multifreq slot is not supported. See the examples section for plotting the multifreq slot using the Logolas package.

See compare_motifs() for more info on comparison parameters.

Note: score.strat = "a.mean" is NOT recommended, as view_motifs() will not discriminate between two alignments with equal mean scores, even if one alignment is longer than the other.

Value

A ggplot object. If return.raw = TRUE, a list.

Author(s)

Benjamin Jean-Marie Tremblay, b2tremblay@uwaterloo.ca

References

\insertRef

logolasuniversalmotif

\insertRef

ggseqlogouniversalmotif

See Also

compare_motifs(), add_multifreq()

Examples

1
2
3
4
5
6
7
8
## plotting multifreq motifs:
## Not run: 
  motif <- create_motif()
  motif <- add_multifreq(motif, sample_sites(motif))
  Logolas::logomaker(motif["multifreq"][["2"]], type = "Logo",
                     color_type = "per_symbol")

## End(Not run)

universalmotif documentation built on April 8, 2021, 6 p.m.