Error in Constraining Symbolic Variables

2011 1 27
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I'm having trouble constraining a symbolic variable to a specific set of numbers.
Example:
(input)
>> syms k positive
will result in (output)
??? Error using ==> mupadinit at 35
Unable to initialize kernel
Error in ==> mupadengine.mupadengine>mupadengine.evalin at 117
[res,status] = mupadmex(statement,8);
Error in ==> mupadeval at 18
result = evalin(symengine,statement,'char');
Error in ==> sym.sym>sym.sym/assumptions at 619
mupadeval(['assume(' s ' > 0):']);
Error in ==> sym.sym>sym.sym/symchar at 203
assumptions(x,a);
Error in ==> sym.sym>sym.sym at 120
S = cell2sym(S,symchar(x,a,nargin));
I have also tried entering this as k=sym('k','positive') to the same effect. I don't understand why this is happening. Also, inputting the command "clear all" has the following effect.
>> clear all
Warning: The following error was caught while executing 'mupadengine' class destructor:
Error using ==> mupadinit at 35
Unable to initialize kernel
I am worried the code may be corrupted for some reason. If someone could provide insight into my issue or help me correct it, I would be greatly appreciative.

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Paulo Silva
Paulo Silva 2011-1-27
Both ways work fine here with matlab 2008b
Matthew
Matthew 2011-1-27
I'm in R2009a, would this not work in a student version? "syms x y" will work fine, it just when i try and constrain them it freaks out.
Oleg Komarov
Oleg Komarov 2011-1-27
Can you post more code? Like what you do before trying to constrain them?
Matthew
Matthew 2011-1-27
There's not anything else before that, I just want to create a variable and constrain it to a certain number set and it keeps giving me errors back to either "mupadengine" or "symengine".

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Walter Roberson
Walter Roberson 2011-1-27

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I would recommend re-installing the symbolic toolbox.

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Matthew
Matthew 2011-1-27
how do i do this?
Walter Roberson
Walter Roberson 2011-1-27
http://www.mathworks.com/help/base/install/pc/ch1_ind2.html#brhzmcm-1
shows how to install specific products

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