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Subject: Re: Faster symbolic computations
Date: Tue, 3 Feb 2009 16:43:02 +0000 (UTC)
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Hi Alan,

Thanks for your response. We'll I'm actually using a mix of numerical inputs with symbolic values. When those meet in my code, the output is symbolic. That's exactly what I wish, namely, a symbolic function having a few variables I specify. It would be easier if I knew the ultimate expression beforehand, because I would be able to simply numerically evaluate it. Because of the complexity and generality in my routine, that's not the case. An alternative would be to have absolutely everything as symbolic, and then evaluate only the variables I want in the very end. That sounds like a better idea; I'm going to try it.

I did take a look at the link you suggested, but it seems that matlabFunction is only useful for the case of numerical evaluation of all variables. In my case, I want to keep a select few as symbolic.

The reason why I suggested changing the value of digits is that I imagined my code would be processed faster if the huge fractional expressions, which crop up in symbolic mode, can be replaced by an approximate "symbolic floating-point" representation having less significant digits. That's all.

Regards,

Thiago