Release 0.9.3 "Transfigured" - Documentation, bug fixes

[c3d]

This release keeps improving the documentation based on the original HP50G Advanced Reference Manual, and fixing issues that are found along the way. It also improves statistics support and adds low-level array manipulation.

New features

• Add PredX, PredY and ΣLine commands for linear regression predictions.
  • The PredX command predicts the independent value from the dependent one.
  • The PredY command predicts the dependent value from the independent one.
  • The ΣLine command returns the regression formula.
• Add Median command to compute the median of statistics series
• Add low-level array manipulation commands, COL+, COL-, ROW+, ROW-, CSWP and RSWP, to add, remove and swap rows or columns.

Bug fixes

• Strip trailing zeros from decimals converted from integers, in order to avoid producing incorrectly normalized values. For example, 70000 converted to decimal now produces a 5-bytes decimal value and no longer a 6-bytes decimal value. This fixes the result of the SigDig command on this input value, as well as fixes cases where comparisions would be incorrect.
• Accept quoted names in == and same. HP calculators evaluate A and B in 'A' 'B' == but not in 'A' 'B' same.
• Add symbolic support for logical operations, i.e. correctly create an expression for 'X' 3 and instead of a type error.
• Compute linear regression for each mode when running BestFit. The previous implementation would erroneously compute the correlation with various modes (linear, log, exp and power), but without optimally recomputing the parameters with that mode.
• Consume arguments in XCol, YCol and ColΣ
• Write slope and intercept in the correct order when updating ΣPar. The order was wrong, causing various commands to either update them in the wrong order, or to swap them.
• Do not emit an error if the stack is empty when running Σ-
• Fix and optimize parsing of ==
• Fix a bug in decimal comparisions used by sqrt and cbrt, fixes the computation of the last digits of sqrt(163) at 24-digit precision.
• Compute log with 3 additional digits to avoid getting the last digit wrong in 'ln(640320^3+744)/sqrt(163)'
• Compute exp, exp10, log and log10 with additional internal digits to make sure that the last digit is good (verifiied using calc).
• Fix sign error in buoyancy equation for Champagne bubbles
• Fix ppar parsing and premature validty checking, which caused 20 30 XRNG to fail because of a transient state where xmin<xmax was not verified.
• expression: Fix rare GC bug in expression::simplify

Improvements

• Compute all decimal functions with increased precision. The tests now check that the last digit of the functions result for the tested input is correctly rounded.
• Add type value for xlib objects in HP compatibility mode
• Add TruthLogicForIntegers flag for compatibility with HP calculators when evaluating something like 42 and 4. DB48x by default computes this bitwise, which returns 0, a logically False value. With the new compatibility flag, the arguments are interpreted as truth values, and the computation produces True for improved compatibility with HP calculators.
• Add RPL programming examples in the documentation, lifted from the HP50G Advanced Reference Manual, covering conditional statements such asIF, IFT, IFTE, documentation about tests and conditional structures, type tests, logical commands such as and, or, not.
• Add documentation and menu entry for Header command
• Add documentation about local variables and the scope of local variables
• Add tests for statistics operations
• Optimize retention of slope and intercept in BestFit
• Micro-optimization on stack operation for comparisons
• Add MSolvr alias for SolverMenu for compatibility with HP calculators
• Allow nested precision adjustments in decimal::precision_adjust class
• Tests now display failures in a way that makes it easier to compare.
• Add documentation for SeparatorModesMenu entries
• runtime: Add check that we push only valid objects
• runtime: Cleanup, remove leftovers from earlier debug
• runtime: Add check for pointer validity
• runtime: Add utility to dump GC pointers
• arithmeric: Add recorder entry to record what operations happen
• Update copyright year to 2025 in VERSION command

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This discussion was created from the release Release 0.9.3 "Transfigured" - Documentation, bug fixes.