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From: rkb@po.CWRU.Edu (Robert K. Brunner)
Newsgroups: comp.sys.handhelds
Subject: A different EQ Lib question
Message-ID: <1991Apr6.163740.18138@usenet.ins.cwru.edu>
Date: 6 Apr 91 16:37:40 GMT
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Reply-To: brunner@uirvld.csl.uiuc.edu (Robert K. Brunner)
Organization: Case Western Reserve University, Cleveland, Ohio, (USA)
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There has beene something bothering me about the EQ library card
for some time.  The problem occurs with the SIDENS utility function.
The solid-state equations in the library use it extensively to calculate
the intrinsic density of states for Si at a given temperature.  The problem
is that it does not give the same value as the textbook I am using
for a class I am taking.  For example, at 300K, the book says 1.45x10^10 cm^-3
but SIDENS gives 1.355x10^10.  I realize that the function is not wrong;
SIDENS is a very steep function of T, so T=300.8K gives 1.45x10^10 cm^-3, which
is pretty close to 300K.  The problem is that it doesn't give me the same
numbers as the professor expects, making the EQ card equations useless.
I have not found a way to override the SIDENS value.  Unlike constants,
you cannot override a rom function definition (or can you).

Now that I think about it, I guess it wouldn't make too much difference
to use T=300.8K whenever I want T=300K.  It just bothers me.

Robert