Many thanks for pointing this out Michel. I must admit that this is proving to be much more complicated than I thought... Reading Hans' "ThisWay" document makes it appear that getting usable bold-faced math fonts is only a few lines of definitions... perhaps I should just look at buying the lucida collection. For the moment, I've settled on a compromise of using: \definefontsynonym [Fourier-Math-Letters] [futr8t] [encoding=ec] and \definefontsynonym [Fourier-Math-Letters-Bold] [futmib] [encoding=ec] With this I can get bold greek symbols (both upper and lower case) but as you pointed out, operators will be italicized if one isn't careful. Sigh.
Now (one of) the difference between fourier and computer modern is that capital greek is in the "italic" font not in the operators font.
This is handled in math-fou.tex:
\definemathsymbol [Gamma] [alpha] [mi] ["00] ....
In an earlier reply, you suggest that I define: \definefontsynonym [Fourier-Math-Letters-Bold] [futb8t] [encoding=ec] but doing so doesn't work as the capital greek symbols... I'm a little confused why the substitutions defined in math-fou.tex are not applied in this case? I need bold \Gamma and \Xi characters in my equations which is why I began looking at all this. I did read through math-fou.tex and mat-lbr.tex but didn't follow some of the definitions. I don't understand why the \definemathsymbol definitions are not applied in this case? I tried to find insight in math-lbr.tex but just got confused.
Note that futmi, and futmii (or futmib futmiib) are two versions of the same font (same encoding): the difference is that in futmmii all is slanted (even greek caps), and in futmii caps are upright (roman and greek) and lowercase are slanted.
I finally realized that when I remembered the existance of \showfont earlier today. This also helped me see where the \definemathsymbol statements in math-fou.tex come from.
If you want command definitions in math-fou.tex to be used even in boldmath, you must change type-spe.tex by referencing the fou math collection in boldmath too.
I'm not sure I follow. My type-spe.tex contains: \starttypescript [math,boldmath] [fourier] [special] \usemathcollection[fou] \stoptypescript Many thanks for your help. Randall