You could try local

local %;

c:=20%
                    20 %

c*3;

                    60 %

I'm not sure, maybe someone saw it as a duplicate question and deleted one of them.  I hate it when people do that, some answers contained in one may be different than one contained in another + looks like you put a lot of work into an answer and someone just blinked it out of existance.

I created something a while back.  See here

https://www.mapleprimes.com/posts/97195-Wordle-In-Maple

SIR model without DE's. 

Here are the equations. 

S_n = S_n-1 - ( ( S_n-1 / S ) * ( β * I_n-1 ) )  # Number of susceptible people

I_n = I_n-1 + ( S_n-1 /S ) * ( B * I_n-1 ) - ( I_n-1 * γ )  # Number of infected people

R_n = R_n-1 + ( I_n-1 * γ )  # Number of recovered people

γ - rate of recovery
β - rate of infection

So for your model 45 days (I've heard a recovery rate of 2 weeks) so the rate of recovery would be 1/45 = 0.022.  I think for the infection rate, for the U.S. it's doubling about every 2.5 days so here the rate is 1/2.5 = 0.4 (Australia's rate is actually just slightly less than 4days)

Hope this helps.

Here is a rope simulation in Maplesim. 

https://www.maplesoft.com/products/maplesim/ModelGallery/detail.aspx?id=121

n link pendulum is I believe what you would use for a rope.  There is a small discussion linked from here https://www.mapleprimes.com/questions/140946-Simulate-Cutting-A-Rope  which points to here https://www.mapleprimes.com/maplesoftblog/6889-An-Animated-Discussion-About-Pendulums

I'll also reference a paper here https://recipp.ipp.pt/bitstream/10400.22/8798/4/ART_MachadoTenreiro252_2015.pdf

This link might be more helpful http://www.pas.rochester.edu/~rrubenza/projects/RR_PHY235W_TermPaper.pdf

For your interest, here is a list of windows preview supported file types.  As you can see there are no maple supported file types

Documents: csv, doc, docm, docx, dotx, eml, msg, odp, ods, odt, pdf, pot, potm, potx, pps, ppsx, ppt, pptm, pptx, rtf, vsd, vsdx, xls, xlsb, xlsm, xlsx

Images: ai, arw, bmp, cr2, eps, erf, gif, ico, icon, jpeg, jpg, mrw, nef, orf, pict, png, psd, tif, tiff

Video: 3gp, m4v, mov, mp4, wmv

3D: 3mf, fbx, obj, ply, stl

Medical: dcm, dcm30, dic, dicm, dicom

Text and code: abap, ada, adp, ahk, as, as3, asc, ascx, asm, asp, awk, bash, bash_login, bash_logout, bash_profile, bashrc, bat, bib, bsh, build, builder, c, c++, capfile, cc, cfc, cfm, cfml, cl, clj, cls, cmake, cmd, coffee, cpp, cpt, cpy, cs, cshtml, cson, csproj, css, ctp, cxx, d, ddl, di, dif, diff, disco, dml, dtd, dtml, el, emakefile, erb, erl, f, f90, f95, fs, fsi, fsscript, fsx, gemfile, gemspec, gitconfig, go, groovy, gvy, h, h++, haml, handlebars, hbs, hcp, hh, hpp, hrl, hs, htc, hxx, idl, iim, inc, inf, ini, inl, ipp, irbrc, jade, jav, java, js, jsp, jsx, l, less, lhs, lisp, log, lst, ltx, lua, m, make, markdn, markdown, md, mdown, mkdn, ml, mli, mll, mly, mm, mud, nfo, opml, osascript, out, p, pas, patch, php, php2, php3, php4, php5, phtml, pl, plist, pm, pod, pp, profile, properties, ps1, pt, py, pyw, r, rake, rb, rbx, rc, re, readme, reg, rest, resw, resx, rhtml, rjs, rprofile, rpy, rss, rst, rxml, s, sass, scala, scm, sconscript, sconstruct, script, scss, sgml, sh, shtml, sml, sql, sty, tcl, tex, text, textile, tld, tli, tmpl, tpl, txt, vb, vi, vim, wsdl, xhtml, xml, xoml, xsd, xsl, xslt, yaml, yaws, yml, zsh

In Maple V R4 it is possible to specify multiple light sources.  This suggests that if one wants to deal with multiple light sources one must revert, at most, all the way back to Maple V.

How is it possible that as Maple gets more powerful we loose functionality?  And it's not just one version, it's many of the new versions where multiple lighting is not possible (if it is, please show me the workaround I am very interested if there is one).  I'm not saying Maple V is more powerful than maple 2019 but with respect to lighting .. it actually is! 

A[..,1]

          [4, 9, 6]

A[..,2]

          [2, 1, 8]

You could try this option here

https://www.mapleprimes.com/posts/200446-3D-Implicit-Plot-With-Scaled-Axes 

I'm actually not sure if this will work, don't have acces to Maple. 

Try th option LINESTYLE(1)

The answer of your expr is never -'ve.  So sign(expr) will give 1 and not -1.

Yes, if you use back quotes around your primed variable.

`A'`:=t

You can select cells and merge using options with the left click section by section. 

Here is a roadmap - a template if you will

`#mscripts(mi("H"),none(),none(),none(),none(),mn("3"),mn("9"))`[7]^2

Easier, you could do ...

assume(x>0)

simplify(combine(f,trig))