I want to write a script that replaces all $$ ... $$ math formulas with \ [... \] in texstudio

Question

Ask people to help me write a script that replaces all the math formulas $$ ... $$ into \ [... ] in texstudio. Thank you!

Answer 1

Here are a few ways that might help to get you started.

We'll start with the following file, say myfile.tex:

myfile.tex

before text $$a^2+b^2=4$$ and $$c^2$$

$$
d^2+e^2 = f^2
$$
and also $$ g^2
$$ and some inline math: $h^2$

in each of the following, the output is:

output.tex

before text \[a^2+b^2=4\] and \[c^2\]

\[
d^2+e^2 = f^2
\]
and also \[ g^2
\] and some inline math: $h^2$

option 1: a perl one liner

perl -p0 -e 's/\$\$(.*?)\$\$/\\\[$1\\\]/sg' myfile.tex > output.tex

See https://perldoc.perl.org/perlrun.html, for example, for details of perl switches.

option 2: using a perl script

Using the following script, and the command

perl replace.pl myfile.tex > output.tex

replace.pl

#!/usr/bin/env perl

use strict;
use warnings;

# read the file into the Document body
my @lines;
my $fileName = $ARGV[0];

# if the file exists, read it into an array
if(-e $fileName){
    open(MAINFILE, $fileName) or die "Could not open input file, $fileName";
    push(@lines,$_) while(<MAINFILE>);
    close(MAINFILE);
} 

# join the lines up
my $body = join("",@lines);

# make the substitution
$body =~ s/\$\$
           (.*?)
           \$\$/\\\[$1\\\]/sgx;

# output the body
print $body;

exit(0);

option 3: using latexindent

Using latexindent which should be available as part of your LaTeX distribution, you can use the following YAML settings file:

Anh.yaml

replacements:
  -
    substitution: |-
     s/\$\$
       (.*?)
       \$\$/\\\[$1\\\]/sgx

and then call it with

latexindent.pl -rr -l=Anh.yaml myfile.tex -o=output.tex