# how to automatic mathbold all capital letters?

Every time I write a capital letter in mathmode I want it in bold.

E.g. I want to write $B$ is a matrix and $b$ a scalar and not to write $\mathbf{B}$ is a matrix and $b$ a scalar but having the same result:

How to do it? :D

• It might be possible, but are you sure you never want a vector space V? Oct 23 '17 at 20:16
• Maybe but almost all capital letters in my thesis are being in bold. I guess I could switch off the autobolding at some part of the document and switch on it in another. Oct 23 '17 at 23:44

\documentclass{article}
\DeclareSymbolFont{bfletters}{OT1}{cmr}{bx}{n}
\DeclareSymbolFontAlphabet{\mathbf}{bfletters}

\DeclareMathSymbol{A}{\mathalpha}{bfletters}{A}
\DeclareMathSymbol{B}{\mathalpha}{bfletters}{B}
\DeclareMathSymbol{C}{\mathalpha}{bfletters}{C}
\DeclareMathSymbol{D}{\mathalpha}{bfletters}{D}
\DeclareMathSymbol{E}{\mathalpha}{bfletters}{E}
\DeclareMathSymbol{F}{\mathalpha}{bfletters}{F}
\DeclareMathSymbol{G}{\mathalpha}{bfletters}{G}
\DeclareMathSymbol{H}{\mathalpha}{bfletters}{H}
\DeclareMathSymbol{I}{\mathalpha}{bfletters}{I}
\DeclareMathSymbol{J}{\mathalpha}{bfletters}{J}
\DeclareMathSymbol{K}{\mathalpha}{bfletters}{K}
\DeclareMathSymbol{L}{\mathalpha}{bfletters}{L}
\DeclareMathSymbol{M}{\mathalpha}{bfletters}{M}
\DeclareMathSymbol{N}{\mathalpha}{bfletters}{N}
\DeclareMathSymbol{O}{\mathalpha}{bfletters}{O}
\DeclareMathSymbol{P}{\mathalpha}{bfletters}{P}
\DeclareMathSymbol{Q}{\mathalpha}{bfletters}{Q}
\DeclareMathSymbol{R}{\mathalpha}{bfletters}{R}
\DeclareMathSymbol{S}{\mathalpha}{bfletters}{S}
\DeclareMathSymbol{T}{\mathalpha}{bfletters}{T}
\DeclareMathSymbol{U}{\mathalpha}{bfletters}{U}
\DeclareMathSymbol{V}{\mathalpha}{bfletters}{V}
\DeclareMathSymbol{W}{\mathalpha}{bfletters}{W}
\DeclareMathSymbol{X}{\mathalpha}{bfletters}{X}
\DeclareMathSymbol{Y}{\mathalpha}{bfletters}{Y}
\DeclareMathSymbol{Z}{\mathalpha}{bfletters}{Z}

\begin{document}

$b + B + c + C$

\end{document}

• Very Thanks :D. Do you know how to make it switchable? in order that at some other point in the document I can write in not bold capital letters in mathmode ? Oct 23 '17 at 23:57