Release 0.9.1 "Follow" - Finances, bit-counting and constants

[c3d]

This release follows-up on 0.9.0 by improving the way constants are evaluated to better serve the equation library. It also adds finance-related functions, and specialized bit-counting functions.

New features

• Add standard and relative uncertainty for all constants. For a constant like G, which when edited looks like ⒸG, the standard uncertainty is ⓈG and the relative uncertainty is ⓇG. This shows as UsG and UrG on screen, to match common practice.

• The constants menu now contains helpers to enter constants, and for the commands Const, StdUnc and RelUnc, which generate a constant, a standard uncertainty or a relative uncertainty from a name.

• Implement precision-control functions that make it possible to adjust the result of computatoins adjusting to relative or standard uncertainty. →Us and →Ur convert betwen standard and relative uncertainty. StandardRound, RelativeRound and PrecisionRound round a value based on its standard or relative uncertainty, or according to the precision of some other value.

• Add bit-counting operations. FirstBitSet and LastBitSet find the position of the first and last bit set in an integer value. CountBits counts the number of bits set in an integer value.

• Add finance operations. The finance menu TVM now shows a solver for time value of money, with payments at beginning (TVMBeg) or at end (TVMEnd). The Amort command generates the amortization (principal, interest and balance). The AmortTable, a DB48x extension, generates a complete amortization table. A new setting, FinanceRounding, a DB48x extension, sets the rounding of finance results.

• Add the Sub command to extract a subset of texts, lists or grobs. As an illustration, the Anagram program was added to the demo state. As a side effect, the named variants for arithmetic operators have been renamed from sub, mul and div to subtract, multiply and divide.

Bug fixes

• Avoid possible crash when using the delete key while searching.

• Fix a few broken (obsolete) links in the help file.

• UVal now works on numbers, not just on unit objects, like on HP calculators.

• Remove NewRPL names for some commands like ToRectangular, and replace them with the DB48x spelling.

Improvements

• Constants are brought up to date to the latest best practice from the scientific community. This includes computing many derived constants from a smaller subset of exact constants, as well as providing standard and relative uncertainty for each constant.

• Constant values are cached to accelerate their evaluation. This avoids having to parse and evalute constant definitions.

• The ConstantMenus was reorganized with more constant categories covering dates, mathematics, chemistry, phsyics, particle masses, electromagnetism, atomic sizes, Compton scattering, magnetism, materials and computing.

• The MathMenu was reorganized, notably to make the exp and log functions easier to access. This merges the former PowerMenu and ExpLogMenu so that the MathMenu still has less than 18 entries.

• Numerical integration now uses the refinements documented in Kahan's 1980 HP Journal article about numerical integration on the HP34. This makes it possible for example to integrate 'sin(x)/x' over 0 to π interval.

• Numerical integration now limits its precision to the number of digits being displayed, like on HP calculators.

• Document the difference and rationale for parsing quoted names compared to HP calculators.

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This discussion was created from the release Release 0.9.1 "Follow" - Finances, bit-counting and constants.