# Libertine Font Greek Letters Size

As you can see the greek letters from pxfonts are bigger than the numbers. How can i fix the size? The numbers size is the better.

\documentclass{article}
\usepackage[T1]{fontenc}
\usepackage[lining]{libertine}
\usepackage[libertine, cmintegrals]{newtxmath}

\DeclareSymbolFont{greeksymbols}{OML}{pxmi}{m}{it}

\DeclareMathSymbol{\beta}{\mathalpha}{greeksymbols}{12}
\DeclareMathSymbol{\gamma}{\mathalpha}{greeksymbols}{13}
\DeclareMathSymbol{\theta}{\mathalpha}{greeksymbols}{18}

\begin{document}

$5\beta +5\gamma+ 2\theta+3\Gamma + 250\log_2 n = 75\sin x$

\end{document}

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note that the height of "l" in "log" is the same as the height of the "Gamma". the digits are shorter than tall letters. – barbara beeton Apr 20 '14 at 15:19

You should use npxmi rather than pxmi, since the former has better metrics. Moreover it allows to set a scaling factor:

\documentclass{article}
\usepackage[T1]{fontenc}
\usepackage[lining]{libertine}
\usepackage[libertine, cmintegrals]{newtxmath}

\makeatletter
\def\npxmath@scaled{.94767}
\makeatother

\DeclareSymbolFont{greeksymbols}{OML}{npxmi}{m}{it}

\DeclareMathSymbol{\beta}{\mathalpha}{greeksymbols}{12}
\DeclareMathSymbol{\gamma}{\mathalpha}{greeksymbols}{13}
\DeclareMathSymbol{\theta}{\mathalpha}{greeksymbols}{18}

\begin{document}

$5\beta +5\gamma+ 2\theta+3\Gamma+ 250\log_2 n = 75\sin x$

\end{document}


The scaling factor 0.94767 has been computed by not setting \npxmath@scaled and measuring the height of \beta and of \Gamma: I got 6.88pt for \beta and 6.52pt for \Gamma. With the scaling factor set, I get 6.52pt for both.

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thanks. i have one more question. if i add \DeclareMathSymbol{\Gamma}..., this give me italic font. how can i make it uppercase. Also do you think it is convenient setting the factor ".9" instead of ".94767". – mert Apr 20 '14 at 13:52
@mert I think it better not to tamper with the fonts; by default the uppercase (upright) Gamma is not taken from the same font as the lowercase Greek letters. If I use the correct font, which should be npxmia, I don't get a really different glyph: just the final serif is slightly different. – egreg Apr 20 '14 at 14:00
@mert Note that the serifs in \Gamma are similar to the ones in Libertine, while the \Gamma from the pxmath font has a different serif. – egreg Apr 20 '14 at 14:05