<html><head></head><body><div style="font-family: Verdana;font-size: 12.0px;"><div>> This is wrong. You're resetting \textfont1. You need to set \textfont\gpfam.</div>
<div> </div>
<div>Like I said, \gbfam and \gbifam (in this case) are numbers:</div>
<div> </div>
<div>\tracingonline=1</div>
<div>\showthe\gbifam</div>
<div>\showthe\gbfam</div>
<div> </div>
<div>--></div>
<div> </div>
<div> </div>
<div>This is TeX, Version 3.141592653 (TeX Live 2022/dev/Debian) (preloaded format=tex)<br/>
(./ttemp.tex<br/>
> 8.<br/>
l.32 \showthe\gbifam<br/>
<br/>
? <br/>
> 9.<br/>
l.34 \showthe\gbfam</div>
<div>
<div> </div>
<div>They are thus family 8 and 9, respectively and \textfont\gbifam and \textfont\gbfam are equivalent to \textfont8 and \textfont9, respectively.</div>
<div> </div>
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<div style="margin:0 0 10px 0;"><b>Gesendet:</b> Sonntag, 27. August 2023 um 17:48 Uhr<br/>
<b>Von:</b> Laurence.Finston@gmx.net<br/>
<b>An:</b> "Gérald Tenenbaum" <gerald.tenenbaum@univ-lorraine.fr><br/>
<b>Cc:</b> "Eplain" <tex-eplain@tug.org><br/>
<b>Betreff:</b> Aw: Re: [tex-eplain] boldface greek symbols</div>
<div name="quoted-content">
<div style="font-family: Verdana;font-size: 12.0px;">
<div>
<div>%% Normal italic:</div>
<div> </div>
<div>\newfam\gbifam<br/>
\font\gbiten=cmmi10<br/>
\font\gbieight=cmmi10 scaled 800<br/>
\font\gbiseven=cmmi10 scaled 700<br/>
\def\gbi{\fam\gbifam\gbiten}</div>
<div>\textfont\gbifam=\gbiten<br/>
\scriptfont\gbifam=\gbieight<br/>
\scriptscriptfont\gbifam=\gbiseven</div>
<div> </div>
<div>%% Bold italic:</div>
<div> </div>
<div>\newfam\gbfam<br/>
\font\gbten=cmmib10<br/>
\font\gbeight=cmmib10 scaled 800<br/>
\font\gbseven=cmmib10 scaled 700</div>
<div>\textfont\gbfam=\gbten<br/>
\scriptfont\gbfam=\gbeight<br/>
\scriptscriptfont\gbfam=\gbseven</div>
<div>\def\gb{\fam\gbfam\gbten}</div>
<div> </div>
<div>Normal Italic: $\gbi{\Delta_\Omega}$</div>
<div> </div>
<div>Bold Italic: $\gb{\Delta_\Omega}$</div>
<div> </div>
<div>\bye<br/>
</div>
<div>See ttemp.dvi (attached)</div>
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<div style="margin: 0 0 10.0px 0;"><b>Gesendet:</b> Sonntag, 27. August 2023 um 17:19 Uhr<br/>
<b>Von:</b> Laurence.Finston@gmx.net<br/>
<b>An:</b> "Gérald Tenenbaum" <gerald.tenenbaum@univ-lorraine.fr><br/>
<b>Betreff:</b> Aw: Re: [tex-eplain] boldface greek symbols</div>
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<div style="font-family: Verdana;font-size: 12.0px;">
<div>> \def\gp{\fam\gpfam\textfont1=\tengp}</div>
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<div>This is wrong. You're resetting \textfont1. You need to set \textfont\gpfam.</div>
<div> </div>
<div>If you create a new family, you shouldn't need to write macros for the individual characters. They should be in the proper positions in the font, if the font is encoded using the conventions of plain TeX.</div>
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<div style="margin: 0 0 10.0px 0;"><b>Gesendet:</b> Sonntag, 27. August 2023 um 15:44 Uhr<br/>
<b>Von:</b> "Gérald Tenenbaum" <gerald.tenenbaum@univ-lorraine.fr><br/>
<b>An:</b> Laurence.Finston@gmx.net<br/>
<b>Cc:</b> "Eplain" <tex-eplain@tug.org><br/>
<b>Betreff:</b> Re: [tex-eplain] boldface greek symbols</div>
<div>
<div style="font-family: Lucida Sans;font-size: 12.0px;">
<div style="font-size: 12.0px;font-family: Lucida Sans;">Thank you.<br/>
<br/>
Here is indeed a working example<br/>
<div style="margin-left: 40.0px;">\input eplain<br/>
\font\tengp=cmmib10<br/>
\newfam\gpfam<br/>
\textfont\gpfam=\tengp<br/>
\def\gp{\fam\gpfam\textfont1=\tengp}<br/>
\def\gth{\hbox{$\gp\vartheta$}}<br/>
$\gth\neq\vartheta$<br/>
\end</div>
<br/>
However this would require distinct definitions for the same letter in distinct sizes.<br/>
The behavior therefore radically departs from standard use in which you can do, for instance,<br/>
<br/>
\font\tenscaln=eusm10 <br/>
\font\sevenscaln=eusm10 scaled 700<br/>
\newfam\scalnfam\textfont\scalnfam=\tenscaln\scriptfont\scalnfam=\sevenscaln<br/>
\def\scaln{\fam\scalnfam\tenscaln}%<br/>
\def\scal{\scaln}<br/>
\def\A{{\scaln A}}<br/>
\def\B{{\scaln B}}<br/>
$\A_\B$<br/>
<br/>
Regards,<br/>
<br/>
Gérald<br/>
<br/>
<span><a class="moz-txt-link-abbreviated" href="mailto:Laurence.Finston@gmx.net" onclick="parent.window.location.href='mailto:Laurence.Finston@gmx.net'; return false;" target="_blank">Laurence.Finston@gmx.net</a> a écrit le 27/8/23 à 15:13 :</span>
<blockquote>
<div style="font-family: Verdana;font-size: 12.0px;">
<div>First, you define a new family using \newfam. This takes care of the problem that Philip brought up, because your new \boldgreek or \bg or whatever macro will change the family within its scope. I think you can have 11 families or so and plain tex only uses 7 or something. I don't remember the details. It would be like this:</div>
<div> </div>
<div>\newfam\boldgreekfam</div>
<div>\def\boldgreek{\fam\boldgreekfam\tenboldgreek}</div>
<div> </div>
<div>\newfam just assigns a number. If you know the number, you could use it instead of \boldgreekfam, but it's better not to.</div>
<div> </div>
<div>Then you set \textfont, \scriptfont and \scriptscriptfont. You might need to use scaling if this font isn't available in the sizes you need. </div>
<div>For example, \font\fiveboldgreek=cmboldgreek10 scaled 700.</div>
<div> </div>
<div>I haven't tested this, so you may have to fiddle with it and/or refer to _The TeXbook_ (never a bad idea).</div>
<div> </div>
<div>That is my attempt to answer your question. My opinion is that it might be difficult to distinguish bold Greek characters in subscripts from ordinary Greek characters and that \bf and \rm are meant to be the exceptions rather than the rule. However, to each his/her own.</div>
<div> </div>
<div>If you have any problems, I'll be happy to try to make a working example.</div>
<div>
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<div style="margin: 10.0px 5.0px 5.0px 10.0px;padding: 10.0px 0 10.0px 10.0px;border-left: 2.0px solid rgb(195,217,229);">
<div style="margin: 0 0 10.0px 0;"><b>Gesendet:</b> Sonntag, 27. August 2023 um 12:44 Uhr<br/>
<b>Von:</b> "Gérald Tenenbaum" <a class="moz-txt-link-rfc2396E" href="mailto:gerald.tenenbaum@univ-lorraine.fr" onclick="parent.window.location.href='mailto:gerald.tenenbaum@univ-lorraine.fr'; return false;" target="_blank"><gerald.tenenbaum@univ-lorraine.fr></a><br/>
<b>An:</b> <a class="moz-txt-link-abbreviated" href="mailto:Laurence.Finston@gmx.net" onclick="parent.window.location.href='mailto:Laurence.Finston@gmx.net'; return false;" target="_blank">Laurence.Finston@gmx.net</a><br/>
<b>Cc:</b> "Eplain" <a class="moz-txt-link-rfc2396E" href="mailto:tex-eplain@tug.org" onclick="parent.window.location.href='mailto:tex-eplain@tug.org'; return false;" target="_blank"><tex-eplain@tug.org></a><br/>
<b>Betreff:</b> Re: Aw: Re: [tex-eplain] boldface greek symbols</div>
<div>
<div style="font-family: Lucida Sans;font-size: 12.0px;">
<div style="font-size: 12.0px;font-family: Lucida Sans;">So how would it work with bold greek?<br/>
When I tried this I get an error until I insert \hboxes<br/>
<br/>
<span><a class="moz-txt-link-abbreviated" href="mailto:Laurence.Finston@gmx.net" onclick="parent.window.location.href='mailto:Laurence.Finston@gmx.net'; return false;" target="_blank">Laurence.Finston@gmx.net</a> a écrit le 27/8/23 à 12:12 :</span>
<blockquote>
<div style="font-family: Verdana;font-size: 12.0px;">
<div>> Can't one design a setting working like \bf or \it ?</div>
<div> </div>
<div>Sure. This is how \bf is defined in plain.tex:</div>
<div> </div>
<div>\newfam\bffam \def\bf{\fam\bffam\tenbf} % \bf is family 6<br/>
\textfont\bffam=\tenbf \scriptfont\bffam=\sevenbf<br/>
\scriptscriptfont\bffam=\fivebf</div>
<div>
<div>
<div style="margin: 10.0px 5.0px 5.0px 10.0px;padding: 10.0px 0 10.0px 10.0px;border-left: 2.0px solid rgb(195,217,229);">
<div style="margin: 0 0 10.0px 0;"><b>Gesendet:</b> Sonntag, 27. August 2023 um 11:41 Uhr<br/>
<b>Von:</b> "Gérald Tenenbaum" <a class="moz-txt-link-rfc2396E" href="mailto:gerald.tenenbaum@univ-lorraine.fr" onclick="parent.window.location.href='mailto:gerald.tenenbaum@univ-lorraine.fr'; return false;" target="_blank"><gerald.tenenbaum@univ-lorraine.fr></a><br/>
<b>An:</b> "Philip Taylor (Hellenic Institute)" <a class="moz-txt-link-rfc2396E" href="mailto:P.Taylor@Hellenic-Institute.Uk" onclick="parent.window.location.href='mailto:P.Taylor@Hellenic-Institute.Uk'; return false;" target="_blank"><P.Taylor@Hellenic-Institute.Uk></a><br/>
<b>Cc:</b> "Eplain" <a class="moz-txt-link-rfc2396E" href="mailto:tex-eplain@tug.org" onclick="parent.window.location.href='mailto:tex-eplain@tug.org'; return false;" target="_blank"><tex-eplain@tug.org></a><br/>
<b>Betreff:</b> Re: [tex-eplain] boldface greek symbols</div>
<div>
<div style="font-family: Lucida Sans;font-size: 12.0px;">
<div style="font-size: 12.0px;font-family: Lucida Sans;">Thanks.<br/>
Yes it suffices, but I also need these boldface letters in subscripts.<br/>
I am puzzled by the necessity of using \hbox. Can't one design a setting working like \bf or \it ?<br/>
Regards,<br/>
<br/>
Gérald<br/>
<br/>
<span>Philip Taylor (Hellenic Institute) a écrit le 27/8/23 à 11:21 :</span>
<blockquote>
<div class="moz-cite-prefix">You don't appear to be using <tt><font size="+1">\gpfam</font></tt>, Gérald — will not the following suffice ?</div>
<p><br/>
<tt>\font \tengp = cmmib10</tt><br/>
<tt>\def \gp {\textfont 1 = \tengp}</tt><br/>
<tt>\def \gth {\hbox {$\gp \vartheta $}}</tt><br/>
<tt>$\gth \neq \vartheta $</tt><br/>
<tt>\end</tt></p>
<p>--<br/>
<i>Philip Taylor</i></p>
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