I want to write in math mode the real part of a complex number and I used the command \mathcal{R}(i). The problem is that the R it produces is not the same as the R in most books that represent the real part. One reason is that it is small and it shouldn't be as it is not meant as a letter but as a symbol. Using the \mathcal{F} I had the same problem representing the Fourier Transform. What command do you use and you think is best and most beuatiful for there operations?
[Tex/LaTex] Representing real part of a complex number and Fourier Transform symbol
symbols
Related Solutions
There is a general way of converting a character to its char number (which is equivalent to its unicode glyph slot in unicode), but it unfortunately doesn't work well in options to fontspec/unicode-math (an issue I'm aware of). Usually you can use something like this:
\newcount\foo
\foo=`\e
to assign the char number of "e" to \foo; this "backtick-escape" syntax works wherever TeX expects a number. However, it doesn't work if the argument is being expanded first, which is what happens in fontspec & unicode-math.
Now, you don't actually need the backslash in the code above; this will work too:
\foo=`e
The difference is that this cannot be used for "difficult" characters such as % and #. If you're just using letters, this won't be a problem.
So in unicode-math you should be able to write
range={`e,`j,...}
Or with whatever letters you need.
The character bounding box of \Box is wrong, the height is too low, when latexsym is used as package to get the symbol:
\documentclass{article}
\usepackage{amsmath,latexsym}
\begin{document}
\setlength{\fboxsep}{0pt}
\setlength{\fboxrule}{.1pt}
\[ \fbox{$\Box$} \fbox{$\hat\Box$} \fbox{$\tilde\Box$} \]
\begin{align*}
\Box &= \sum_a \partial^a\partial_a \,, &
\hat\Box &= \sum_a \mathcal{D}^a\mathcal{D}_a
\end{align*}
\end{document}
Using amssymb instead fixes the issue:
\documentclass{article}
\usepackage{amsmath,amssymb}
\begin{document}
\setlength{\fboxsep}{0pt}
\setlength{\fboxrule}{.1pt}
\[ \fbox{$\Box$} \fbox{$\hat\Box$} \fbox{$\tilde\Box$} \]
\begin{align*}
\Box &= \sum_a \partial^a\partial_a \,, &
\hat\Box &= \sum_a \mathcal{D}^a\mathcal{D}_a
\end{align*}
\end{document}
Best Answer
Please choose what you like. If you are not able to use Lua- or XeLaTeX, let me know.