Release 0.9.6 "Peace" - Bug fixes

This release is mostly bug fixes

Bug fixes

• Evaluate index in get and put like the HP50G
• Avoid premature simplification during arithmetic operations
• Do not wrap variables after Copy, e.g. in 'A+A▶A+A'
• Return errors for unknown primitives / derivatives in algebraics
• Correctly use GraphicResultDisplay for result stack level
• Ensure pi and e display the same size at 60 digits precision
• Fix bogus exponent truncation in polynomials
• Fix issue in + and - on vectors with angles, e.g. [ 3 2 1.7_° ]
• Fix possible garbage collection memory corruption in FromVector

Improvements

• units: Make BaseUnits, →Deg, →Rad, →Grad and →πr array-wise
• Add VectorMenu on first page of MatrixMenu
• Do not single-step or debug during plot/integration
• Add routine to render u64 and i64

Release 0.9.5.1 "Wait" - Emergency fix for Wait and Refresh

Bug-fix only release for timing of Wait command

Bug fix

The changes that improve battery life in 0.9.5 had an impact on commands that need absolute time, because the internal timer of the DM32/DM42 switches of when in deep sleep. As a result, Wait with durations longer than 1 second would wait much longer than expected, and long-duration Refresh settings e.g. BatteryRefresh would also wait longer than expected. Replace the use of the internal timer with a synthetic timer based on the real-time clock.

Release 0.9.5 "Everlasting" - Power management, offline graphics

This release brings two major new features: vastly reduced power drain, and off-line persistent graphics.

New features

• Off-line graphics are the ability to draw images in memory instead of directly on screen. Like on HP calculators, this works by storing a graphic object in PICT. Unlike HP calculators, PICT is an actual variable in the current directory, meaning that you can have multiple PICT, although bitmaps use a lot of memory. For example, running 500 300 BLANK 'PICT' STO will create a 500x300 pixels off-line image in PICT, and all graphic commands after that will draw in that off-line image instead of on screen. Off-line graphics are not immediately shown on screen, but are displayed before returning to the command line in a way similar to the Show command (i.e. centererd if smaller than the screen, and with scrolling if larger). They are also persistent, meaning that you need to explicitly ClLCD to erase them.
• Add Blank, BlankGrob, BlankBitmap and BlankPixmap commands to create a blank image with default format, in HP GROB format, in DB48x bitmap (Black and white) format and in DB50x pixmap format (color RPL only).
• Add →HPGrob, →Bitmap, →Pixmap commands which can be used to generate an HP-compatible GROB format, a bitmap or a pixmap (color RPL only) from an object. If the object is already a graphic, perform conversion. Note that on color RPL, conversions between color and monochrome formats are supported. Colors are converted to monochrome using grayscale patterns.
• Add →LCD and LCD→ commands to send an object to the current graphics, or to create a graphic object from the current screen content.
• The Off command can now be used in a program and will preserve what is on screen. You can resume execution of the program by using the ON key. Add PowerOffWithImage command to show off-images even from programs.

Bug fixes

• Fix display of object Info in the interactive stack
• Clear system timers before entering system menu, so that the self test menu entry does not run a fast-paced loop.
• Fix off-by-one error in result of LastBitSet (number bits starting at 0)
• Correctly render color pixmaps when on the stack (color RPL only)

Improvements

• Reduce power usage dramatically by disabling timers when going to sleep. This manifests as a higher battery voltage being shown, which is closer to what the DM42 firmware or integrated self-test would show. This will most likely improve battery life for interactive uses of DB48x.
• Reorganize the MemoryMenu to make both GC and runtime statistics available
• Reorganize the GraphicsMenu by topics to accomodate the new commands
• Add image checks in the test infrastructure for RPL code examples
• Add tests for RGB colors
• Repair make compare which was trying to build a binary from compare.cc
• Make Sub a compatibility spelling for Extract, not the default one
• Adjust low battery indications to avoid premature warnings
• Make debug_printf use lower-level routines that can run earlier after boot
• Add make INSTALL_PGM_ONLY=y install option for faster install
• Generate DB48x bitmaps by default instead of HP-compatible GROBs. Bitmaps use less memory when the width is not a multiple of 8.
• Make test of pixel functions more reliable by increasing their timeout
• Add help for ModesMenu, SymbolicResults and NumericalResults

Release 0.9.4 "Face, meet palms" - Pixmaps, bug fixes

This release fixes embarassing numerical bugs introduced in 0.9.3 and introduces a new pixmap type intended to capture screen pixel maps including in color. Builds for hardware calculators are also smaller due to switching to a nano configuration for the compiler.

New features

• graphics: Add pixmap type

Bug fixes

• Adjust unit conversion in StdRnd
• Fix parsing of ΣY² in equations
• Render non-fancy large exponents correctly (e.g. 1E123456789012345)
• The precision of numerical constants now adjusts after changing PREC
• Avoid unnecessary purging of constants cache due to internal precision changes
• Return tests values to rounded valus as validated with Wolfram Alpha
• directory: Fix STOVX and Store to non-current directories

Improvements

• Fix sqrt precision, notably for perfect squares (ouch)
• Improve support for recent ARM compilers
• Eliminate new clang warnings
• Eliminate warnings about function pointers in latest XCode
• Add documentation for DisplayModesMenu
• Precision adjustments are now more consistent across decimal functions

Release 0.9.3 "Transfigured" - Documentation, bug fixes

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

Release 0.9.2 "Temptations" - Multi-variate solver, documentation

This release introduces a true multiple-variables solver, additional matrix operations, and extends the RPL programming documentation.

New features

• The Root command now selects a true multi-variable solver (Jacobian solver), capable of solving systems of equations with multiple variables, even when variables cannot be isolated one at a time, for example solving { 'sin(x)=y' 'sin(y)=x+1' }. As a result, the DB48x Root command now covers the functionality provided by the HP50G's ROOT, MROOT and MSLV .
• Compatibility for MSLV is preserved thanks to a dedicated command, which like the HP50G leaves input equations and variables on the
  stack.
• Add RNRM and CNRM (row and column norms) commands for matrices.
• Add TRN and TRAN commands (matrix transpose, with or without conjugate)

Bug fixes

• Add several missing images used by the test suite to the git repository, e.g. for the TVM menu.
• Fix rare bug parsing lists causing a validation error
• Fix theoretical risk of memory corruption in det
• Solutions found by the solver no longer depend on the existence and value of global variables by the same name prior to solving
• Emit "Interrupted" error when interrupting the solver
• Fix bug comparing decimal zero with small decimal values

Improvements

• Add a section with RPL programming examples, seeded with examples from Chapter 1 of the HP50G Advanced Reference Manual.
• Add documentation about program objects, text, symbols and comments.
• Update documentation for complex numbers, e.g. ℝ→ℂ command.
• Add documentation for abs
• Add links to "Rules" in constant uncertainty section
• Add a few additional tests in the documentation
• Split instrumentation for the three solver algorithms.
• The solver now uses the display precision to limit the precision of the desired result, like the integrator and like HP calculators.

Video demo: https://www.youtube.com/watch?v=hj-LGN2nhzU

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

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.

Release 0.9.0 "Wilson's Dream" - Full equation library

This version integrates an extended version of the HP50G equation library that Jean Wilson has been working on for many weeks. Equations are also fully documented, with examples illustrating how to use them, and a full documentation of the variables they contain.

It also fully enables the algebraic-assisted solver, i.e. a version of the solver that attempts to isolate variables to evaluate expressions directly, which is both faster and more accurate when possible.

WARNING Equations in the current state of the library are not fully validated yet. DB48x users are invited to test them and report issues they find.

WARNING Constants used in the library are relatively accurate and have been modernized compared to the HP50G version. However, an effort is underway to compute the physical constants that are not fundamental but derived from other constants. It is expected that the numerical values returned from the equations will changeslightly as constants are udpated.

Features

• Improved equation library and documentation The equation library now features more than 650 equations, more than 700 variables, 18 sections and 158 subsections. This is roughtly twice as big as the HP50G equation library, and covers more modern aspects of science such as nuclear physics.

Bug fixes

• solver: Do not propagate errors during isolate When using the algebraic-assisted solver, errors raised by the internal calls to isolate no longer manifest as solver errors.
• units: Do not leave error behind in unit::convert_to_real This could cause spurious Inconsistent units errors while solving.
• logical: Make logical operations behave symmetrically, i.e. ensure that #100+1 and 1+#100 both return #101.
• nfunctions: Evaluate symbolic arguments symbolically and fix bugs converting arguments to decimal. The evaluation of '∫(0;1;x+1;x)' after x=3 would result in a nonsensical expression '∫(0;1;4;3)'.
• integrate: Report errors in bound evaluation. An error in the evaluation of the first bound could be "erased" if the evaluation of the second bound was successful. For example, in '∫(0;1;sin(x)/x;x)', the Divide by zero error evaluating 'sin(x)/x' at x=0 is erased by the successful evaluation at x=1 that follows.

Improvements

• equations: Accept units in isolate This allows many equations in the equation library to successfully use the symbolic approach, improving accuracy significantly.
• add/sub: Accept zero as an operand around units. An operation like 1_km+0 is now accepted, and evaluates as 1_km.

Signed-off-by: Christophe de Dinechin christophe@dinechin.org

Release 0.8.11 "Accomplishment" - Towards full equation library

This release contains a number of fixes and features intended for use in the equation library being contributed by Jean Wilson

Features

• Accept library items for functionc calls. For example, the expression 'ⓁSiDensity(273_K)' is now accepted. This function is usd in semi-conductor equations in the library.
• The Root command now attempts symbolic solving using the Isol command. This can lead to exact solutions for common equations.
• The SigDig command is a DB48x extension that returns the number of significant digits in a number, i.e. the number of non-zero digits.
• The xpon and mant now apply to unit objects
• Functions now accept assignments as input, e.g. x=9 sqrt gives 3.0
• The equation referenced to by the Equation variable can now be identified using a name.
• The NxEq command now works with quoted equations

Bug fixes

• The ln(1E-100) expression no longer gives a Argument outside domain error. The error was caused by rounding during argument reduction.
• Comparison between a value and a unit object now work correclty
• Arithmetic now correctly deals with dimensionless unit objects, for example in expression '1-1000_mm/m', and improves the evaluation of unit expressions when adding or subtracting unit objects.
• Names containing programs or functions are now evaluated as part of algebraic evaluation
• The solver now correctly processes equations wrapped in an expression.
• Convert now correclty evaluates its arguments when necessary
• Assignment objects no longer cause a crash on error. For example, x='ln(0)' no longer crashes.

Improvements

• Improve solver heuristic when slope is small. This allows the solver to find a solution for an equation like 'tan(x)=224' in degrees mode.
• Add more recorder entries in the solver describing what is being solved.
• Move recorder entries for tests to tests data logger.
• Tests use a larger text rendering limit
• Tests now purge the directory between examples. This prevents stray variables from influencing later tests.
• The handling of long UTF-8 sequences in tests was improved, which allows tests involving a lot of text (e.g. examples) to run faster.

Release 0.8.10 "Fire Dove" - Input and Prompt, Android preparation

The focus of this release is support for user input in programs, with the addition of the Input and Prompt commands. Internally, a lot of groundwork was performed towards Android builds.

New features

• Add Prompt command, which programs can use to let users manipulate the stack or do other operations before resuming execution.

• In order to facilitate the use of Prompt, added the Run command, which resumes execution of halted programs and otherwise evaluates the first item on the stack. The key at the left of the + key, which is labeled R/S on the DM-42 calculators, is now bound to the Run command instead of Evaluate. Therefore, after a Prompt, you can resume execution with a single key.

• Add Input command, which programs can use to let users enter data. The DB48x version makes it easier to enter and validate numerical data or other non-text objects, with input validators for numbers, integer values, arithmetic objects or expressions. It is also possible to use custom code to validate user input.

• Additional Compile variants were created to help with this user input validation, checking if the input is a number, an integer, a positive integer, a real number, a single object, a single algebraic object or an expression.

Bug fixes

• Fixed problem with the computation of the length of the integer value being parsed if it was parsed from a text value at the end of the temporaries.

• Emit an error from Step and variants if no program is being debugged. The effect was that the next program being run would halt after the first step.

• Avoid persisting beep in the simulator when two beeps were emitted rapidly in successioon.

• Reload the user-selected keymap file after loading the state file.

Improvements

• Change capitalization of DTag as a shortcut for DeleteTag.

• Various code improvements making it easier to compile for Android. A side effect is that the simulator can now safely be started from any current directory.

• Improve rescaling of the window in the simulator to keep the keyboard and screen larger and easier to read.

• Improve the detection of the default simulator size for Hi-DPI screens.

• Add documentation about matrix multiplication performance

• Make the default memory size more consistent with the simulated device.