> Csikos Bela <mailto:bcsikos425@freemail.hu>
> 14. Oktober 2016 um 16:56
> Wolfgang Schuster írta:
>
>>> I would like to set up Tex Gyre Adventor sans serif
>>> font as my math font (even if it doesn't havemath symbols). I have
>>> two questions related to this problem.
>>>
>>> 1. In latex I can specify
>>> math font versions, define a specific font as math serif / normal,
>>> another as mathsans serif etc.
>>> (http://milde.users.sourceforge.net/LUCR/Math/math-font-selection.xhtml).
>>> Is this possiblein context, and if yes, how?
>> ConTeXt doesn’t use the same style switches as LaTeX.
>
> Thanks. Is there a way to change font family locally in math mode?
> For example how can I use serif if sans serif is the default math font?
It depends what you want to achieve, for string you can use \text{...} 
which uses the text font.
>> 3. You can use the font fallback mechanism to replace certain character
>> in the math font with characters from a text font.
>>
>> \definefontfamily     [mathfont] [rm] [Tex Gyre Bonum]
>> \definefallbackfamily [mathfont] [mm] [Tex Gyre Adventor]
>> [preset=math:lowercaseitalic]
>> \definefallbackfamily [mathfont] [mm] [Tex Gyre Adventor]
>> [tf=style:italic,range=0x068,offset=0x0210E]% Planck constant
>> \definefontfamily     [mathfont] [mm] [Tex Gyre Pagella Math]
>>
>> \setupbodyfont[mathfont,10pt]
>>
>
> I played a lot with these setups and have questions.
> I use this font setting:
>
> \definefontfamily     [docuf] [rm] [TeX Gyre Bonum]
> \definefontfamily     [docuf] [ss] [TeX Gyre Adventor]
> \definefontfamily     [docuf] [tt] [Latin Modern Mono] [features=none]
>
> \definefallbackfamily [docuf] [mm] [Tex Gyre Adventor] [preset=math:uppercasenormal]%,scale=.6]
> \definefallbackfamily [docuf] [mm] [Tex Gyre Adventor] [preset=math:uppercasebold]%,scale=.6]
> \definefallbackfamily [docuf] [mm] [Tex Gyre Adventor] [preset=math:uppercaseitalic]%,scale=.6]
> \definefallbackfamily [docuf] [mm] [Tex Gyre Adventor] [preset=math:uppercasebolditalic]%,scale=.6]
>
> \definefallbackfamily [docuf] [mm] [Tex Gyre Adventor] [preset=math:lowercasenormal]%,scale=.6]
> \definefallbackfamily [docuf] [mm] [Tex Gyre Adventor] [preset=math:lowercasebold]%,scale=.6]
> \definefallbackfamily [docuf] [mm] [Tex Gyre Adventor] [preset=math:lowercaseitalic]%,scale=.6]
> \definefallbackfamily [docuf] [mm] [Tex Gyre Adventor] [preset=math:lowercasebolditalic]%,scale=.6]
>
> \definefallbackfamily [docuf] [mm] [Tex Gyre Adventor] [preset=math:digitsnormal]%,scale=.6]
> \definefallbackfamily [docuf] [mm] [Tex Gyre Adventor] [preset=math:digitsbold]%,scale=.6]
> \definefallbackfamily [docuf] [mm] [Tex Gyre Adventor] [preset=math:digitsitalic]%,scale=.6]
> \definefallbackfamily [docuf] [mm] [Tex Gyre Adventor] [preset=math:digitsbolditalic]%,scale=.6]
>
> \definefontfamily     [docuf] [mm] [TeX Gyre Pagella Math]
>
> \setupbodyfont[docuf,24pt]
>
> 1. If I want to use a scale factor is it possible the give the scale factor by using
> the preset a,b,c,d,x,xx values? Or I must specify the scale factors as numbers?
Only numbers are possible.
> 2. Scaling occurs compared to which font in the definition list?
>
> 3. I found that if I write \definefontfamily     [docuf] [mm] [TeX Gyre Pagella Math]
> before \definefallbackfamily lines, the latter have no effect. Is this normal?
> Shouldn't the order of definition lines be indifferent?
The fallbackfamily settings are applied to a typeface and the 
\definefontfamily commands creates
the typeface, without \definefontfamily the fallbacks are never used 
because there is no font which
can use the settings.
> 4. If I write a paragraph with different font size, how can I scale the embedded math
> too automatically? For example if I write
>
> \placefigure[here]{Figure title}{\ss\tfxx
> A B C D \math{E~F~G~}}
>
> A B C D is typeset with small fonts but E F G not; it will be huge compared to
> A B C D. I can't manually scale the math part because it is inserted here
> by chemfig module and I can't redefine how it typesets fonts.
The x and xx perform not the same scaling as a, b etc. but you can 
define your
own sizes which behave the same way as a etc.

\definefontsize[m]
\definefontsize[n]

\definebodyfontenvironment[default][m=0.8,n=0.9]

\starttext

{\tfm This paragraph contains text and $math$.}

{\tfn This paragraph contains text and $math$.}

This paragraph contains text and $math$.

{\tfa This paragraph contains text and $math$.}

{\tfb This paragraph contains text and $math$.}

\stoptext

Wolfgang