Package 'latexr'

Extract the AST of a LaTeX formula.

Description

Runs the same scanning and parsing pipeline used by latex2r(), but returns the parsed abstract syntax tree instead of the R translation. Useful for debugging formulas and for tooling that wants to inspect the structure recognized by the parser.

Usage

latex2ast(x)

Arguments

x

string

Value

An Expr object, or NULL (invisibly) when the formula can't be scanned.

Examples

latex2ast("\\beta_1^{2}")

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Construct R function from LaTeX expression.

Description

Construct R function from LaTeX expression.

Usage

latex2fun(latex_string, envir = parent.frame(), na.rm = FALSE)

Arguments

latex_string	string
envir	environment
na.rm	boolean; when TRUE, calls to mean() and median() are emitted with na.rm = TRUE.

Value

function

Examples

x = seq(-2 * pi, 2 * pi, length.out = 500)
f = latex2fun("\\sin{x * a}")
f_x = f(x = x, a = 2)
plot(x, f_x, type = "l")

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Translate LaTeX formula to R code.

Description

Take a LaTeX formula and attempts to find an equivalent representation in R. If interactive=TRUE it pops up an interactive REPL that does the same, but interactively.

Usage

latex2r(x, interactive = FALSE, na.rm = FALSE)

Arguments

x	string
interactive	boolean
na.rm	boolean; when TRUE, calls to mean() and median() are emitted with na.rm = TRUE.

Value

string

Examples

latex2r("\\beta_1^{\\frac{x+1}{x^2 \\cdot y}}")
latex2r("\\bar{x}", na.rm = TRUE)

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Normalize Unicode characters to their LaTeX equivalents.

Description

Converts the Unicode characters commonly emitted by visual formula editors (MathQuill, embedded in many learning platforms) or by plain keyboard input into the LaTeX commands understood by latex2r().

Usage

normalize_mathquill(x)

Arguments

x

string

Details

Minus signs and dashes become -, the multiplication and division symbols become ⁠\times⁠, ⁠\cdot⁠ and /, Greek letters become the corresponding LaTeX commands, and accented vowels become ⁠\bar{}⁠, ⁠\tilde{}⁠ or ⁠\hat{}⁠ (or their base letter when the accent has no meaning here).

This function is applied automatically by latex2r() before scanning, but it is exported so callers can inspect the normalized version of a formula.

Value

string

Examples

normalize_mathquill("×")

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Print a Token object.

Description

Print a Token object.

Usage

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

Arguments

x	A Token object.
...	Further arguments passed to or from other methods.

Value

The string representation of the token, invisibly.

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