Order terms in symbolic poly converted to string

Is there a way to control the order of the terms in a symbolic polynomial that has been converted to string?
E.g. the following
syms x
T=taylor(exp(x),order=3);
string(T)
results in
ans = "x + x^2/2 + 1"
and I would rather have it as 1+x+x^2/2 or the reverse order. I'll be putting this in the title of a plot so if there is some other way to automatically get the correct order in the title that would work equally as well.

 Respuesta aceptada

Liam Ivers
Liam Ivers el 18 de Jul. de 2024
Editada: Liam Ivers el 18 de Jul. de 2024
Use the sympref function to change the display of the symbolic polynomial:
I noticed that the string function does not update with this change(A = "x + x^2/2 + 1"), but it does if you use the latex command (B = '1+x+\frac{x^2}{2}') which may look better for plot headings.
syms x
T=taylor(exp(x),order=3)
sympref('PolynomialDisplayStyle','ascend')
A = string(T)
B = latex(T)
titletext = ("$" + latex(T) + '$')
title(titletext,Interpreter='latex')

2 comentarios

@Ethan Duckworth, Consider trying this "what-you-see-is-what-you-get" direct approach.
sympref("PolynomialDisplayStyle", "ascend");
syms x
T = taylor(exp(x), order=3)
T = 
titletext = ("$" + latex(T) + '$');
fplot(T), grid on
title(titletext, Interpreter='latex')
Weird that string(T) doesn't preserve the order of the terms, but that latex(T) does!

Iniciar sesión para comentar.

Más respuestas (1)

James Tursa
James Tursa el 18 de Jul. de 2024
Editada: James Tursa el 18 de Jul. de 2024
Brute force if you need the string for some reason?
syms x
ex = taylor(exp(x),order=3)
ex = 
[C,T] = coeffs(ex)
C = 
T = 
terms = fliplr(C.*T)
terms = 
n = numel(terms);
s = char(terms(1));
for k=2:n
c = char(terms(k));
if( c(1)=='-' )
s = [s ' - ' c(2:end)];
else
s = [s ' + ' c];
end
end
s
s = '1 + x + x^2/2'

1 comentario

Wholy cow! That works, but the shorter approach by @Liam Ivers is the one I accepted.

Iniciar sesión para comentar.

Categorías

Más información sobre Creating and Concatenating Matrices en Centro de ayuda y File Exchange.

Preguntada:

el 17 de Jul. de 2024

Comentada:

el 18 de Jul. de 2024

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by