Dear Andrew, thanks for the excellent idea. I will be a true believer and user once it works smoothly.

Nevertheless, I have just tried a simple sum and the following error is presented at compilation time: ! Undefined control sequence. \clyx_vvlist_process:NN ...ist #1\clist_reverse:N \l_tmpb_clist \clist_map_i... l.25 \calculyx{$\sum_{n=1}^{2}n$} No result of this sum is shown in the preview. Did I do something wrong? Regards, ------------------------------------------------- Julio Rojas jcredbe...@gmail.com On Mon, Nov 24, 2014 at 7:23 AM, Murat Yildizoglu <myi...@gmail.com> wrote: > Very nice and very cool indeed! Thanks a lot Andrew! This seems to be a > nice (also because much lighter) competitor to the Sage module for many > numerical computations. I will check it as soon as I can. > Best regards, > > Murat > > aparsloe <apars...@clear.net.nz> > 24 novembre 2014 02:47 > I've written a LaTeX package called "calculyx" which numerically evaluates > mathematical expressions in LyX "before one's eyes" using instant preview. > It is written in the expl3 language of LaTeX3 but is used just like any > other LaTeX package. There is a link at > http://wiki.lyx.org/Examples/Calculyx to a zipped archive currently in a > Dropbox folder, and a screenshot (.png format) of a one-page LaTeX document > and the resulting pdf with a few example calculations at > https://www.dropbox.com/s/7djkyjs44bpraol/Screenshot%202014-11-24%2013.52.07.png?dl=0. > The LaTeX may look complicated, but using LyX, all that is as ever hidden. > One simply enters expressions in the LyX math editor as usual. > > Calculyx requires the three LaTeX3 bundles l3kernel, l3packages and > l3experimental. Because a main routine uses a command that was introduced > to l3kernel on 18 July 2014, the version of l3kernel must be later than > this. The calculational engine for calculyx is the floating point module > l3fp in l3kernel. > > I have tried to ensure as much as possible that calculyx reads expressions > as mathematicians write them. For instance it will "digest" \sin 3x - 3\sin > x + 4\sin^{3} x (for a specified value of x, say \pi/6) without parentheses > around the arguments and with the superscript in the "wrong" but familiar > place. It will "digest" the common arithmetic operators, plus variants like > \times and \div, the familiar trigonometric and hyperbolic functions and > their inverses, the exponential and natural logarithm, fractions (\frac, > \tfrac), square root and \surd, factorials ( using !), binomial > coefficients (\binom, \tbinom), \gcd, sums and products (\sum, \prod) > including "infinite" sums and products, limits (\lim), derivatives (1st and > 2nd order), including Cartesian 2-d and 3-d Laplacians, and definite > integrals in one variable. Results are generally presented in the form: > expression = result. There is also a (multi-column) table creating command > and another which will iterate a function (for the chaos theorists). > > The package contains a novelty that I think could be exploited more > widely. Some calculations are computationally intensive. So as not to > burden the compilation of the pdf with them, these calculations can be > "parked" either in a LyX note or in an inactive branch. Instant preview > works in both places (with a caveat for LyX notes). The result of the > calculation can be saved to a LaTeX control sequence. Calculyx > automatically saves such control sequences to a file. They are then > available for inserting elsewhere in the document -- even at the start, > long before the place where the calculation is performed. If you are > prepared to set up a converter and copier, then the file containing the > control sequences can be saved in the document directory -- or copied to > other directories whereby the results of those "parked" calculations are > made available to these other documents. By this means selected items in > LyX notes or inactive branches can play a part in compilation to pdf. > > Andrew > > > -- > Prof. Murat Yildizoglu > > UniversitĂ© de Bordeaux > GREThA (UMR CNRS 5113) > Avenue LĂ©on Duguit > 33608 Pessac cedex > France > > Bureau : E-331 > > Mail: yildi-at-u-bordeaux4.fr > Web: yildizoglu.info > <yi...@u-bordeaux4.fr> > > >