latex

LaTeX form of symbolic expression

Syntax

chr = latex(S)

Description

chr = latex(S) returns the LaTeX form of the symbolic expression S.

Examples

LaTeX Form of Symbolic Expressions

Find the LaTeX form of the symbolic expressions x^2 + 1/x and sin(pi*x) + phi.

syms x phi
chr = latex(x^2 + 1/x)

chr = 
'\frac{1}{x}+x^2'

chr = latex(sin(pi*x) + phi)

chr = 
'\phi +\sin\left(\pi \,x\right)'

LaTeX Form of Symbolic Array

Find the LaTeX form of the symbolic array S.

syms x
S = [sym(1)/3 x; exp(x) x^2]

S = 
$$\left(\begin{array}{cc}\frac{1}{3}& x\\ {\mathrm{e}}^x& x^2\end{array}\right)$$

chr = latex(S)

chr = 
'\left(\begin{array}{cc} \frac{1}{3} & x\\ {\mathrm{e}}^x & x^2 \end{array}\right)'

LaTeX Form of Symbolic Matrix Variables

Since R2021b

Compute several symbolic matrix variables, and then find their LaTeX form.

Create 3-by-3 and 3-by-1 symbolic matrix variables.

syms A 3 matrix
syms X [3 1] matrix

Find the Hessian matrix of $$X^{T}AX$$. Derived equations involving symbolic matrix variables appear in typeset as they would be in textbooks.

f = X.'*A*X

f = $$X^{\mathrm{T}}\hspace{0.17em}A\hspace{0.17em}X$$

H = diff(f,X,X.')

H = $$A^{\mathrm{T}}+A$$

Generate the LaTeX form of the symbolic matrix variables f and H.

chrf = latex(f)

chrf = 
'{\textbf{X}}^{\mathrm{T}}\,\textbf{A}\,\textbf{X}'

chrH = latex(H)

chrH = 
'{\textbf{A}}^{\mathrm{T}}+\textbf{A}'

Modify Generated LaTeX with Symbolic Preferences

Modify generated LaTeX by setting symbolic preferences using the sympref function.

Generate the LaTeX form of the expression $$\pi$$ with the default symbolic preference.

sympref('default');
chr = latex(sym(pi))

chr = 
'\pi '

Set the 'FloatingPointOutput' preference to true to return symbolic output in floating-point format. Generate the LaTeX form of $$\pi$$ in floating-point format.

sympref('FloatingPointOutput',true);
chr = latex(sym(pi))

chr = 
'3.1416'

Now change the output order of a symbolic polynomial. Create a symbolic polynomial and set 'PolynomialDisplayStyle' preference to 'ascend'. Generate LaTeX form of the polynomial sorted in ascending order.

syms x;
poly = x^2 - 2*x + 1;
sympref('PolynomialDisplayStyle','ascend');
chr = latex(poly)

chr = 
'1-2\,x+x^2'

The preferences you set using sympref persist through your current and future MATLAB® sessions. Restore the default values by specifying the 'default' option.

sympref('default');

Use LaTeX to Format Title, Axis Labels, and Ticks

For $$x$$ and $$y$$ from $$-2\pi$$ to $$2\pi$$, plot the 3-D surface $$y\sin (x)-x\cos (y)$$. Store the axes handle in a by using gca. Display the axes box by using a.Box and set the tick label interpreter to latex.

Create the x-axis ticks by spanning the x-axis limits at intervals of pi/2. Convert the axis limits to precise multiples of pi/2 using round and get the symbolic tick values in S. Display the ticks by setting the XTick property of a to S. Create the LaTeX labels for the x-axis by using arrayfun to apply latex to S and then concatenating $. Display the labels by assigning them to the XTickLabel property of a.

Repeat these steps for the y-axis. Set the x- and y-axes labels and the title using the latex interpreter.

syms x y
f = y.*sin(x)-x.*cos(y);
fsurf(f,[-2*pi 2*pi])
a = gca;
a.TickLabelInterpreter = 'latex';
a.Box = 'on';
a.BoxStyle = 'full';

S = sym(a.XLim(1):pi/2:a.XLim(2));
S = sym(round(vpa(S/pi*2))*pi/2);
a.XTick = double(S);
a.XTickLabel = strcat('$',arrayfun(@latex, S, 'UniformOutput', false),'$');

S = sym(a.YLim(1):pi/2:a.YLim(2));
S = sym(round(vpa(S/pi*2))*pi/2);
a.YTick = double(S);
a.YTickLabel = strcat('$',arrayfun(@latex, S, 'UniformOutput', false),'$');

xlabel('x','Interpreter','latex');
ylabel('y','Interpreter','latex');
zlabel('z','Interpreter','latex');
title(['$' latex(f) '$ for $x$ and $y$ in $[-2\pi,2\pi]$'],'Interpreter','latex')

Input Arguments

S — Input

symbolic number | symbolic variable | symbolic vector | symbolic array | symbolic function | symbolic expression | symbolic matrix variable

Input, specified as a symbolic number, variable, vector, array, function, expression, or symbolic matrix variable (since R2021b).