Is it possible to use the DeclareFontShape command with kpfonts?

Question

In my work, I've been using the fourier package to get a nice typography and I've been capable of add a lot of different types of math text styles

and with a proper size thanks to the \DeclareFontShape command except with the kpfonts' fraktur style. The way that I get this style is with

\DeclareMathAlphabet{\mathfrak}{U}{jkpmia}{m}{it}
\SetMathAlphabet{\mathfrak}{bold}{U}{jkpmia}{bx}{it}

in the preamble but I don't know how to use \DeclareFontShape here because there's not a \DeclareFontFamily command. So...

Is there a way to modify the size of the fraktur style with the code that I provide or is there another way to get this style that allows to use a \DeclareFontShape command or is impossible?

Answer 1

Just scale the Fraktur font by adding s*[0.9] to the \DeclareFontShape where 0.9 is the scaling factor.

\documentclass{article}
\usepackage{fourier}
\DeclareFontFamily{U}{jkpmia}{}
\DeclareFontShape{U}{jkpmia}{m}{it}{<->s*[0.9]jkpmia}{}
\DeclareFontShape{U}{jkpmia}{bx}{it}{<->s*[0.9]jkpbmia}{}
\DeclareMathAlphabet{\mathfrak}{U}{jkpmia}{m}{it}
\SetMathAlphabet{\mathfrak}{bold}{U}{jkpmia}{bx}{it}
\begin{document}
$\mathcal{ABCD} \mathfrak{ABCD}$
\boldmath
$\mathcal{ABCD} \mathfrak{ABCD}$
\end{document}