Converts LaTeX to a plotmath expression.

Description

TeX converts a string comprising LaTeX commands (such as a math equation) to a plotmath expression. Plotmath expressions can be used throught R's graphic system to represent formatted text and equations.

Usage

TeX(
  input,
  bold = FALSE,
  italic = FALSE,
  user_defined = list(),
  output = c("expression", "character", "ast")
)

Arguments

Value

Returns a plotmath expression by default. The output parameter can modify the type of the returned value.

If more than one string is specified in the input parameter, returns a list of expressions.

Adding new commands

New LaTeX commands can be defined by supplying the user_defined parameter. The user_defined parameter is a list that contains LaTeX commands as names, and template strings as values. A LaTeX command that matches one of the names is translated into the corresponding string and included in the final plotmath expression. The file symbols.R in the source code of this package contains one such table that can be used as a reference.

The template string can include one of the following special template parameters:

• $arg1, $arg2, ... represent the first, second, ... brace argument. E.g. for \frac{x}{y}, $arg1 is x and $arg2 is y.

• $opt is an optional argument in square brackets. E.g. for \sqrt[2]{x}, $opt is 2.

• $sub and $sup are arguments in the exponent (^) or subscript (_) following the current expression. E.g. for \sum^{x}, $sup is x.

• $LEFT and $RIGHT are substituted the previous and following LaTeX expression relative to the current token.

See the Examples section for an example of using the user_defined option.

Examples

TeX("$\\alpha$") # plots the greek alpha character
TeX("The ratio of 1 and 2 is $\\frac{1}{2}$")

a <- 1:100
plot(a, a^2, xlab=TeX("$\\alpha$"), ylab=TeX("$\\alpha^2$"))

# create a \variance command that takes a single argument
TeX("$\\variance{X} = 10$", user_defined=list("\\variance"="sigma[$arg1]^2"))

Deprecated; use TeX instead.

Description

Deprecated; use TeX instead.

Usage

latex2exp(string, output = c("expression", "character", "ast"))

Arguments

Value

Returns an expression (see the output parameter).

latex2exp Examples

Description

Plots a number of example LaTeX string, as parsed by TeX.

Usage

latex2exp_examples(cex = 1)

Arguments

Returns the list of supported LaTeX commands.

Description

If show is TRUE, also show a searchable table of symbols.

Usage

latex2exp_supported(show = FALSE, ...)

Arguments

Value

A data frame containing a table of supported LaTeX commands.

Previews a LaTeX equation

Description

Plots the result of a call to [TeX] on the current graphical device. This is useful to preview the output before placing it on a plot.

Usage

## S3 method for class 'expression'
plot(x, ..., main = NULL)

Arguments

Examples

plot(TeX("Example equation: $a \\geq b$"))

Print an expression returned by TeX()

Description

Prints out the plotmath expression generated by TeX and the original TeX string.

Usage

## S3 method for class 'latexexpression'
print(x, ...)

Arguments

Prints out a parsed LaTeX object, as returned by TeX(..., output='ast'). This is primarily used for debugging.

Description

Prints out a parsed LaTeX object, as returned by TeX(..., output='ast'). This is primarily used for debugging.

Usage

## S3 method for class 'latextoken2'
print(x, depth = 0, ...)

Arguments

Renders a LaTeX tree

Description

Returns a string that is a valid plotmath expression, given a LaTeX tree returned by parse_latex.

Usage

render_latex(tokens, user_defined = list(), hack_parentheses = FALSE)

Arguments

Value

String that should be parseable as a valid plotmath expression