document updated 12 years ago, on Aug 23, 2011
A LOT of software calculators out there are button-oriented (AKA immediate execution), which seems kind of silly, since that constraint is a holdover from hardware calculators.
Expression-calculators seem much better. Even better are expression-calculators that allow you to scroll back through history.
These need not be as heavyweight as CAS systems. CAS are very powerful, but aren't remotely lightweight.
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