Why does symbolic output always come out like this?

Why does symbolic output always come out like this? - Messages

#1 Posted: 3/4/2024 6:59:02 AM
Jason McCool

Jason McCool

9 likes in 78 posts.

Group: User

Please see the screenshot below with a comparison between SMath and Mathcad. Mathcad produces the expected output of multiplying a matrix by a vector of variables - a matrix with those variables in the appropriate terms of the matrix. SMath, for all the years I've used it, has never done this well. Setting optimization to symbolic comes close in that the result has the variable placed in each term of the matrix, but symbolic has always been completely useless for me because it always makes everything into these huge weird fractions. Can nothing be done about this?? Surely I am not the only one who finds this frustrating and difficult to work around? Does anyone have any suggestions?

Note: these are not the same calcs, so ignore that the values are numerically different. The Mathcad calc is from a couple of years ago when I could afford Mathcad at their student discount rate, while the SMath calc is from an assignment I'm working on in my current class. My point is about SMath wanting to convert simple decimal numbers to ratios of 40-digit long numbers instead of just leaving them as decimals that 1) obscure what's going on because of there being fractions where there weren't any before, and 2) making the formulas and results unable to fit on a page anymore. If I pick numeric optimization, then it won't display any result because the variables aren't defined yet, and the variables are what I'm solving for. If I pick none, then it condenses it somewhat, but the variables aren't distributed into the matrix and the matrix is now in the form of fractions like 1.57890573210119*10^25 / 8.27641801957219*10^15. Either way, not usable. Any help is appreciated. Thanks!

Smath matrix display.jpg
Jason McCool Robbins Engineering Little Rock, AR, USA
#2 Posted: 3/4/2024 4:51:06 PM
Martin Kraska

Martin Kraska

1222 likes in 2150 posts.

Group: Moderator

If using the Maxima plugin is an option for you, then you can use the float() function along with Optimization> None in SMath.
Note that ratexpand() is not needed here but may be useful for more complex expressions.

Worksheet3.sm (4 KiB) downloaded 32 time(s).
Worksheet3.png
Martin Kraska Pre-configured portable distribution of SMath Studio: https://en.smath.info/wiki/SMath%20with%20Plugins.ashx
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Jason McCool 3/5/2024 9:57:00 AM
#3 Posted: 3/4/2024 9:41:33 PM
Jason McCool

Jason McCool

9 likes in 78 posts.

Group: User

I've installed Maxima and th eMaxima plugin, and I can get the MaximaControl command to work, but "float" isn't a recognized command. Is that function from another plugin?

Edit: Never mind.I think I have it now. Very new to Maxima, but that does what I need. Thanks!
Jason McCool Robbins Engineering Little Rock, AR, USA
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