> > Johannes Kuester <[log in to unmask]> wrote: > > >May be there should be a fourth script-like font, or at least parts of > >an alphabet in such a style, to be used for some special one letter symbols, > >containing for example > > > >P for the power set (also mentioned in J. Ziegler's article) > >C to denote the set of continuous / continuous differentiable functions > > (as in C^k(\mathbf{R}) or the like) > >O and o for the Landau symbols (denoting the order of magnitude of > > a function) > > I am thinking of having perhaps only two (using NFSS terminology) > "scripty" families, one less scripty, like the AMSfonts Euler script, and > one more scripty, looking like handwritten script, which would cover those > symbols mentioned above, both upper/lowe case then. These families would > then come in full (math) series (normal, bold) and shapes (upright, > slanted). (I suppose that `handwritten script' here refers to `Formal Script' (e.g. rsfs fonts), is that correct?) I'll try to be more explicit. One frequent notation of `power set' is to use \mathfrak{P}. Now, if Fraktur is used for e.g. vector spaces, this is ambiguous and should be avoided by escaping to \mathscr{P}. But if Formal Script is used for another concept, one has to use yet another symbol etc. Thus I think it would be better to have a special, reserved symbol for `power set', clearly distinguishable from other `P's. Justin Zieglers proposal contained a position for such a letter (and his article some ASCII art to give an idea of that glyph), and WordPerfect has such a glyph in (one of) its character set(s), though wrongly called `Weierstrass' (no, it is not TeX's \wp for the Weierstrass `p' function, that glyph is there, too (also called `Weierstrass'). Now there are more symbols with the similar problem: how to represent them unambiguously. May be these won't make up a whole alphabet, may be they shouldn't be called a font, as they need not share characteristics, and may be they don't need to have a script-like appearance, but all this doesn't change the mathematical necessity for such symbols, and I think that TeX should provide them (may be after a lengthy discussion about their appearance, as there does't seem to be a design for these symbols except for the power-set-P). Johannes Kuester -- Johannes Kuester [log in to unmask] Mathematisches Institut der Technischen Universitaet Muenchen