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I teach physics at Fullerton College, a community college in Southern California.


Jul
24
awarded  Excavator
Jul
24
revised Conditional typesetting / build
fix broken link
Jul
23
awarded  Yearling
Jul
2
awarded  Curious
Jun
27
comment Package ifpdf Error
This answer fixed one conflict between packages for me in the past, but it later caused a conflict. (After an upgrade to texlive 2013, the package xparse became upset about the fact that \ifpdf was undefined.) Maybe the solution is to complain to package authors rather than to do workarounds of this type.
Jun
27
awarded  Popular Question
Jun
24
answered Does italic math originate from TeX?
Jun
24
awarded  Good Question
Jun
23
accepted Semantics of negative glues
Jun
23
awarded  Nice Question
Jun
23
accepted Mathematical description of TeX's infinite numbers?
Jun
23
comment Semantics of negative glues
Thanks! I think this all makes sense to me now, as explained in my edit to the question, except that I don't really follow the part where you analyze the fifth example and there is "normal glue" that "resurrects."
Jun
23
revised Semantics of negative glues
more work figuring stuff out
Jun
23
comment Mathematical description of TeX's infinite numbers?
Egreg and Ryan Reich pointed out that it's not associative and not a group. However, if one wishes I think this can be taken as a detail of the implementation rather than as a property of the underlying mathematical structure. After all, floating point multiplication is not associative either. Just as a floating-point number is represented in computer memory with truncation to the $n$ most significant digits, we could think of a glue as being stored with only its most significant part.
Jun
23
comment Mathematical description of TeX's infinite numbers?
If I do something like \hskip 0pt plus 2fill x \hskip 0pt plus 3fill, then one could argue that tex is dividing one glue by another glue, resulting in a quotient r=2/3, which is then used in positioning the letter x at 1/(1+r) of the way from the right side. Similarly for \hskip 0pt plus 1fill x \hskip 0pt plus 1filll, you could say that the quotient r is infinitesimally small, and then 1/(1+r) only differs infinitesimally from 1. (Internally, I assume r is represented as 1.)
Jun
23
comment Mathematical description of TeX's infinite numbers?
I made a separate question: tex.stackexchange.com/questions/186215/…
Jun
23
comment Mathematical description of TeX's infinite numbers?
related: tex.stackexchange.com/questions/186215/…
Jun
23
asked Semantics of negative glues
Jun
23
comment Mathematical description of TeX's infinite numbers?
I'm confused about the semantics of negative values: \documentclass{article} \begin{document} \noindent \framebox[80pt]{\hskip 0pt plus 1fill 2 \hskip 0pt plus 2fill} \\ \framebox[80pt]{\hskip 0pt plus 1fill 1 \hskip 0pt plus 1fill} \\ \framebox[80pt]{\hskip 0pt plus 1fill 0.1 \hskip 0pt plus 0.1fill} \\ \framebox[80pt]{\hskip 0pt plus 1fill $-0.5$ \hskip 0pt plus -0.5fill} \\ \framebox[80pt]{\hskip 0pt plus 1fill $-1$ \hskip 0pt plus -1fill} \\ \framebox[80pt]{\hskip 0pt plus 1fill $-2$ \hskip 0pt plus -2fill} \end{document}
Jun
23
comment Mathematical description of TeX's infinite numbers?
In the definition of $\gamma$, items (4) and (5), should those be $o$'s rather than $O$'s?