Hi Fabrice,

I use Lucida OT fonts for all my documents, but since I prefer the script fonts from another font I have the following setups for my font:

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% Some Font Definitions
\definefallbackfamily[myfont][math][Asana Math]
	[range={uppercasescript,lowercasescript}]

% lucida font
\definefontfamily[myfont][serif][Lucida Bright OT]
\definefontfamily[myfont][math][LucidaBrightMathOT]
\definefontfamily[myfont][sans][LucidaSansOT]
\definefontfamily[myfont][mono][LucidaSansTypewriterOT]

\setupbodyfont[myfont,9pt]

%% End of Font Definitions
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

Then when I use for instance the command $\cal{C}$ the script font from Asana Math is used, instead of from Lucida OT.

Best regards: OK

> On 15 Oct 2019, at 21:57, Fabrice Couvreur <fabrice1.couvreur@gmail.com> wrote:
> 
> Hello,
> Thanks to you two. 
> "Another solution is to define your own mixture of math fonts and text fonts."
> I thought you should not mix several fonts in one text. I know you're a teacher, what are you doing to write your documents ?
> Fabrice
> 
> Le mar. 15 oct. 2019 à 19:11, Otared Kavian <otared@gmail.com <mailto:otared@gmail.com>> a écrit :
> Hi Fabrice,
> 
> Wolfgang gave the right answer, but I wanted to point out that it is better not to use \setupbodyfont in the middle of your document, as you did in the excerpt below: in this case it is better to use 
> 
> \switchtobodyfont[xits]
> 
> or even better define the character you want before using it as in
> 
> \define\CScript{\start\switchtobodyfont[xits] \m{\mathscript{C}} \stop}
> 
> and then use that command as in:
> 
> La droite \m{(AM)} est {\bf une sécante} à la courbe \CScript en \m{A}.
> 
> Another solution is to define your own mixture of math fonts and text fonts.
> 
> Best regards: OK
> 
> 
>> On 15 Oct 2019, at 18:39, Fabrice Couvreur <fabrice1.couvreur@gmail.com <mailto:fabrice1.couvreur@gmail.com>> wrote:
>> 
>>  La droite \m{(AM)} est {\bf une sécante} à la courbe {\setupbodyfont[xits]\m{{\mathscript C}}} en \m{A}.
> 
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