getLatexStrWidth
Obtain Font Metrics from LaTeX
These functions calculate the width of a character or string as it would appear after being compiled by LaTeX.
Usage
getLatexStrWidth(texString, cex = 1, face = 1,
engine = getOption("tikzDefaultEngine"),
documentDeclaration = getOption("tikzDocumentDeclaration"), packages,
verbose = interactive(), diagnose = FALSE)getLatexCharMetrics(charCode, cex = 1, face = 1,
engine = getOption("tikzDefaultEngine"),
documentDeclaration = getOption("tikzDocumentDeclaration"), packages,
verbose = interactive())
Arguments
- texString
An arbitrary string for which the width is to be calculated. May contain LaTeX markup.
- cex
a real number that specifies a scaling factor that is to be applied to device output.
- face
an integer in the range
1:5that specifies the font face to use. See par for details.- engine
a string specifying which TeX engine to use. Possible values are 'pdftex', 'xetex' and 'luatex'. See the Unicode section of tikzDevice-package for details.
- documentDeclaration
See the sections "Options That Affect Package Behavior" and "Font Size Calculations" of tikzDevice-package for more details.
- packages
See the section "Options That Affect Package Behavior" of tikzDevice-package.
- verbose
A logical value indicating whether diagnostic messages are printed when measuring dimensions of strings. Defaults to
TRUEin interactive mode only, toFALSEotherwise.- diagnose
pass
TRUEto print detailed error information.- charCode
an integer that corresponds to a symbol in the ASCII character table under the Type 1 font encoding. All numeric values are coerced using
as.integer(). Non-numeric values will not be accepted.
Details
These functions are used internally by the tikz device for proper
string placement in graphics. Both functions check to see if metrics exist
in a global or temporary dictionary (as defined in
options('tikzMetricsDictionary')) and if so will pull the metrics
from there. If the dictionary does not exist, then a temporary one is
created for the current R session. Metrics are calculated via system
calls to LaTeX compilers. Querying compilers to calculate metrics is
expensive and so we strongly recommend setting
options('tikzMetricsDictionary') <- '/path/to/dictionary' to create a
global dictionary.
Value
The width of texString in points.
A numeric vector holding ascent, descent and width. Values should all be nonnegative.
References
PGF Manual
Examples
# NOT RUN {
getLatexStrWidth('{\\\\tiny Hello \\\\LaTeX!}')
# Calculate ascent, descent and width for "A"
getLatexCharMetrics(65)
# }