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cas<->home interchange - Printable Version

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cas<->home interchange - leprechaun - 08-26-2015 12:25 PM

Hello everyone.

I just played with the toolbox of the prime. Tried commands, read help info ans so on.
If I look at cas commands under home view. The calculator seems to notice it. It adds CAS. to the command.

I tried partfrac(). You get CAS.partfrac(). Trying the example under help leads to a syntax error although obviously the prime knows that it has to translate the partfrac() command somehow.
I remember that the trouble with cas/home has been discussed and I remember that I felt like having understood, but I notice I still (or again) am more than lost.

a) How do I take benefit of the CAS.-automatisation? e.g. How do I type in the help-example in home? Or better invoke a quick CAS command?

b) please HP, no matter if it means work: If it IS possible: work on that dark side of the prime. Make usage easier and more intuitive for us poor brains without being forced to start from scratch after some mounths. :-)

P.S. CAS.ifactor(555) works. It has, again, to do with the variables I guess?

RE: cas<->home interchange - Joe Horn - 08-26-2015 02:38 PM

The errors you are seeing is due to the fact that CAS allows undefined variables to be used for symbolic math manipulations, but Home does not. Therefore none of the Help system's examples for CAS functions which have undefined variables in their arguments (e.g. partfrac) will work in Home... and they should not be expected to.

There is an essential difference between Home and CAS; if they were the same, there would be no need for both to exist. Home is for real number crunching, like "What is a 12-digit approximation of the square root of 8?". CAS is for algebraic, symbolic, exact math, like "What is the exact square root of 8?" or "What does (x^2-1)/(x-1) simplify to?" Use the right tool for the right job. Don't use Home for symbolic math.

EDIT: Perhaps it would help if the Help system's built-in examples of CAS functions with undefined variable arguments included a warning: "Do not attempt this at Home." Smile

RE: cas<->home interchange - toshk - 08-26-2015 06:21 PM

Prime can spare us some of the dichotomy [cas<->home interchange] by way it represent final solution. take c/partfrac as a example, i represent the solution without the involvement of variable say x. checkout my app involving rational function, by the way i wrote in #cas mode but can be easily be implemented in Home mode.