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Do we need a CAS-dictionary?

Josef Böhm, ACDCA & Technical University, Vienna, Austria

Eno Tonisson, University of Tartu, Estonia

As Time Goes by … the CAS Might Change!

DERIVE

wxMaxima

TI-NspireCAS

GeoGebra (CAS?)

WIRIS

Others???

YACASMuPad

Voyage 200

MATHEMATICA

Imagine we would like to create a sequence!

In my new school they have a licence for MuPad

In DERIVE I have been used to apply the VECTOR.command:

Switching to TI-Nspire CAS was not so difficult, because I know how to work with the TI-92 and the Voyage 200

But my colleagues insist on working online with WIRIS:

How to create a sequence?

How to create a sequence?

A few schools are working with open source wxMaxima:

And I was recommended to try another open source CAS:

YACAS

How to create a sequence?

You will surely recognize this:

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Integration & Plotting

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A System of linear Equations

(2 Equations and 4 Variables!)

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TI-Nspire

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wxMaxima

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WIRIS

YACAS

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MuPad

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Differences

• Between CAS1 and CAS2• Between CAS1 and school• ?? Between school and school ??

• Input syntax– VECTOR, seq, makelist, table …– 3a, 3*a– a^2, a2

– …

• Output of the results

1tan2 2cos

12][aSec

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One may want to

• Get acquainted with certain CAS

• Compare certain CASs – for example, familiar one and unfamiliar one

• Compare some CASs– choose suitable CAS– research on CASs

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Dictionary (Merriam-Webster)

• : a reference source in print or electronic form containing words usually alphabetically arranged along with information about their forms, pronunciations, functions, etymologies, meanings, and syntactical and idiomatic uses

• : a reference book listing alphabetically terms or names important to a particular subject or activity along with discussion of their meanings and applications

• : a reference book giving for words of one language equivalents in another

• : a computerized list (as of items of data or words) used for reference (as for information retrieval or word processing)

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Model

• Multilingual dictionaries could be taken as the models.

• The commands of certain CAS form the "language" (or "dialect").

• There are several special needs.

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Example of Multilingual Dictionary

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Looking for Platform

• The product should be – web-based, – user-friendly and – open for supplements.

• Open source for dictionary???

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From scratch

• Keywords– relational database– MySQL– Java– servlets– Tomcat

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Main Page for Users

• Select CASs (1..n)

• Select Topic

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“Example Unit”

• Id: 17• CAS: Derive 6• Problem: Solve equation 2x+3=9• Topic: Linear equation, 1 variable, 1 solution• Input: solve(2x+3=9,x)• Comments on input: 2x, 2*x, 2·x are allowed• Output: x=3• Comments on output: • …• …

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Primitive prototype of CASDictionary

• That's one small step for mankind, one giant leap for me

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Next steps

• Depend on your reaction!!!• Possible directions

– Automatic “translation” between CAS languages

– …

• Do we need a CAS-dictionary?• What kind of?• …