Hi Hans,
There are instances where the automatic scaling provided by \left and
\right is not ideal and one has to use manual scaling. For example:
\starttext
\startTEXpage \startformula
\left\langle \sum_{i=1}^n A_i x_i \right\rangle
\hbox{ vs. }
\bigg\langle \sum_{i=1}^n A_i x_i \bigg\rangle
\stopformula \stopTEXpage
\stoptext
Currently, math fences always default to using \left and \right, which can
lead to undesirable results. For example:
\definemathfence [MEAN] [angle] [command=yes, color=blue]
\starttext
\startTEXpage \startformula
\MEAN{ \sum_{i = 1}^n A_i x_i }
\hbox{ vs. }
\bigg\langle \sum_{i=1}^n A_i x_i \bigg\rangle
\stopformula \stopTEXpage
\stoptext
Could we add an option to \definefence that allows the user to select the
delimiter scaling using a key (say, `delimiter`) so that
\MEAN[delimiter=auto] expands to \left\langle .. \right\langle
\MEAN[delimiter=] expands to \langle .. \rangle
\MEAN[delimiter=big] expands to \big\langle ... \big\rangle
\MEAN[delimiter=Big] expands to \Big\langle ... \Big\rangle
\MEAN[delimiter=bigg] expands to \bigg\langle ... \bigg\rangle
\MEAN[delimiter=Bigg] expands to \Bigg\langle ... \Bigg\rangle
I am not sure whether `delimiter` is the best key. I think that `scale`
may be better, but using `scale` for specifying the scaling of math
delimiters will be inconsistent with how `scale` is used everywhere else.
Another option is to use `alternative` key.
Thanks,
Aditya