dCalc - a graphical RPN calculator for Psion/Revo/EPOC


Author's Note
Whats new (3.00)
English versionEnglish Manual
German versionGerman Manual
Version History
Users Comments
English version English
German version Deutsch
French version French
Italian version Italian

  • Version 3.00, Dec 21st 2002
    • New Features:
      • Source code available

  • Version 2.02, Oct 1st 2002
    • New Features:
      • Grad (neugrad) mode added
      • SCI, FIN, STA, PRO functions moved to FILE menu item to make way for grads in MODE
      • degrees/grads/radians are now displayed as units after an INV SIN, INV COS etc function.
      • Interest and number of payments are checked to be non-negative on input and before calculations.
      • More refinements to the interest calculation for fewer failures to converge.
      • French & Italian messages
      • A French help file
    • Bugs fixed:

  • Version 2.01, May 25th 2002 (beta version only, not generally released)
    • New Features:
      • French & Italian messages added
    • Bugs fixed:
      • A much more robust interest rate calculation was implemented

  • Version 2.00, Mar 29th 2002
    • New Features:
      • Support for Drive E:
      • Longer programmable functions (150 characters - was 50)
      • German help file added
    • Bugs fixed:
      • Blank lines in a currency update file would result in a runtime error. Fixed.
      • Ctrl_Shift-F gave runtime error. Fixed.
    • Download

  • Version 2.00b1, Dec 16th 2001
    • German language support

  • Version 1.13.2, Oct 25th 2001
    • programmable keys (f1 f2 f3 f(X) f'(X)) were inoperative after using PRO mode. Fixed.

  • Version 1.13.1, Oct 5th 2001
    • Bugs stomped

      • European users: When using comma as the decimal point (in "System->Control Panel->International->Number" settings), dCalc was unable to read a currency file. Fixed.

      • The currency conversion dialog gave an error message "String too long" when too many currencies were defined. Now, if too many currencies are defined a message will flash at the bottom right of the screen and the currency will be dropped. Sometimes the overflow is due to similar currencies being defined but with different spellings (e.g. "Fr Francs" and "Fr. Francs"). The fix is to use Word to edit C:\System\Apps\Dcalc\Currency.txt (remember to save as a text file) and restart dCalc or (easier) just use the "System" app to delete C:\System\Apps\Dcalc\Currency.txt and import a new currency.upd file.

  • Version 1.13, Sep 23rd 2001
    • New Features
      • There is now a student concession rate for dCalc - see the registation section for details
      • A currency read operation is added - now you can conveniently keep your Psion up to date with world currencies.
      • A currency file is updated daily at http://bhepple.freeshell.org/psion/update.txt
      • Currency file is now saved by dCalc after every manual change or merge.
      • By request of various users:
        • "<" and ">" are now mapped to SHIFTLEFT/RIGHT 1 bit
        • "," (comma) maps to CHS (if "," (comma) is used for the decimal point then "." (full-stop) is mapped to CHS instead)
        • "\" maps to 1/X (reciprocal)
        • "&" now maps to a new function "TOGGLE FLOAT" - toggle between FIX & SCI

    • Bugs stomped
      • In currency edit, the date of the last update is now displayed instead of today's date. This is set to today's date if rates are changed.
      • Std Deviation was in error. Fixed (but it was a tough one to spot!)

  • Version 1.12.1, July 14th 2001
    • New Features

    • Bugs stomped
      • Superfluous stack lift after BSP. Fixed.
      • INV BSP was not translating to CLx. Fixed.
      • H->h.mmss should display 0.0060 as 0.0100. Fixed.

  • Version 1.12, April 28th 2001
    • New Features
      • Fix Sci Eng keys to toggle Fixed, Scientific and Engineering displays
      • .ini file now always kept on C: as D: can be slow
      • reorganise the keyboard so that PROG mode now has x2, INV and yx

    • Bugs stomped
      • Volume conversions failed. Fixed.
      • Fluid ounce conversion was incorrect. Fixed.
      • Prime factor calculation was wrong for simple numbers such as x^n. Fixed.

  • Version 1.11.2 March 23rd
    • Released as a PocketIQ product
  • Bugs stomped
    • The DYS function was in error. Fixed.

  • Version 1.11.1 March 20th (not released)
    • First beta version for PocketIQ

  • Version 1.11 March 10th 2001
    • New features
      • Currency conversions - up to 36 currencies of your choice
      • Added LR Linear Regression (least squares linear function fit) to STA mode. Also, once a LR fit is made, Y can be calculated from X and vice versa.
      • Units are now displayed in all the registers - with an option under 'Preferences' to suppress them. There is a CLu button to temporarily clear the units
      • CLR clear registers button added; clear financial registers becomes CLf. INV CLX now clears just the stack. Clear stats registers is removed - the stats registers are now 1-9 so there seems little point!
      • By popular demand (!) changed Finance keys to n i PV PMT FV
      • In Finance mode, added a DYS Days between dates function. Dates entered as YYYY.MMDD. INV DYS calculates the number of days based on a 30 day month in a 360 day year. There is a TDY button for todays date.
      • Moved ST+ etc to a popup and reduce ST+ ST- ST* ST/ to a single key ST?
      • Icons for SUM SUM- StdD Sqrt Y^X PI
      • Internet Protocol (IP) address display in PRO mode e.g.
      • Convert in PRO mode now pops up a menu
      • Added an HTML version of the manual for PC browsing - not installed on the Psion, just look in the zip file
      • STO+ et al. are now on one key ST? which pops up a menu
    • Bugs stomped:
      • In graphs, Y axis labels & grid interval set to integer values gets corrupted on close/open e.g. 1 to 1.00000057220459. X axis is OK! MinY and MaxY too! Fixed (this appears to be a bug in the Psion OS which I have had to work around - a real lulu!)
      • Interest calculations on Annuity at start was failing. Fixed.
      • Std Dev calculation was incorrect. Fixed.

  • Version 1.10 Feb 10th 2001
    • New features
      • The stack is now clickable - tap a stack number and it exchanges with X
      • Added %CH - percentage change
      • Added STO* and STO/ - store and multiply/divide into register
      • Added CLX = clear X, (INV CLX) does a "Clear All")
      • Added *12, /12 (times and divide by 12) to FIN mode
      • Added d->r decimal radians conversion in SCI mode
      • Screen layout cleaned up e.g. removed LstX and X<>Y keys as they are no longer needed (just click Y Z T or L register to exchange with X)
    • Bugs stomped:
      • XOR and MOD functions in PRO mode gave a "Procedure not found" error. Fixed.
      • Use of "E" key was sometimes blocked in real modes. Fixed.
      • Lifted X display by 2 pixels on the Series 5 to improve readability
      • Provided explanations for keys as well as buttons
      • Improved the menu consistency between calculator and graphing modes
      • Changed the description "Payment at N=0" to "Annuity at period start"
      • Payment at N=0 was giving incorrect results. Fixed.
      • microns were not converted correctly. Fixed.

  • Version 1.9 Jan 6th 2001
    • New features
      • Revo support
      • Better layout of the + - * / and Enter keys
      • French AZERTY keyboard support in addition to QWERTY and MC218
    • Bugs stomped:
      • ctrl-c in graphics mode produced an exception. Fixed.

  • Version 1.8 Dec 31st 2000
    • New features
      • 2 new buttons - Sto+ and Sto- to add to or subtract from a register (replacing Cpy and Pst which are still available as ctrl-c, ctrl-v, from the main menu and from the left "silk screen" menu)
      • Financial calculations of compund interest previously assume that the first payment is made at time N=1 - i.e. at the end of the first period. Now you can make "hire purchase"-type problems where a payment is made at the start of the period - at time N=0. Use Menu->Mode->Payment at N=0 or ctrl-h while in Finance mode to toggle this feature on and off.
      • A new option for MC218 users to remap keyboard so that R=x T=/ Y=+ and U=-. See under Menu->Tools->Hotkey (Ctrl-O)
    • Bugs stomped:
      • problem installing on flash card solved
      • clashes with key assignment of copy/convert and register/graph is resolved
      • Financial functions enter a number more consistently

  • Version 1.7 Oct 20th 2000
    • New features:
      • ability to draw cartesian graphs (i.e. in X and Y)
      • a percent % key in SCI, STA & FIN modes
      • inverse functions for SQR ROOT CUBE C.ROOT %
      • reorganisation of the menu
      • smaller memory footprint (approx 45kbyte - was 65kbyte)

  • Version 1.6 Sept 16th 2000
    • New features:
      • the key "C" maps to "convert" instead of "Clear X"
      • Prime factors calculation added to PROG mode
      • Evaluation period is now extended to 28 days for every release
      • many speedups and a cleaner GUI

  • Version 1.5 August 19th
    • New Features
      • Programmable keys - allows you to use Psion OPL expressions under a dCalc key e.g. create your own key to convert inches to mm ("X*25.4") ... or much more complex functions
      • Newton-Raphson solutions - put your f(x) and f'(x) functions into the programmable keys, put a guess in X and dCalc will iterate to a solution (if there is one!)
      • Permutations and combination calculations in statistics mode
      • By request of European users, hH jJ kK and l are now mapped to multiply, divide, minus and add
      • Exit button on right tab bar is deleted; there is now a shortcut to Convert in its place
      • Exit no longer needs confirmation - all state information is saved
      • A more sensible key layout is used - ABCDF keys are only active in Prog mode; Log, ln, sqrt, pi, e and 1/x keys are only active in non-Prog modes.
      • New mode keys at the top of the screen (for quick access to Finance, Scientific, Statistics and Programming modes)
      • Prettier dialog boxes
    • Bugs stomped
      • entering numbers in PROG mode binary and octal was broken - fixed
      • In PROG mode, ASCII display of a negative number was broken in the leftmost byte. Fixed.
      • r->p was in error for some values of X & Y. Fixed.
      • Std. Dev. calculation was wrong. Fixed.
      • Sum- was not working Fixed.

  • Version 1.4 July 29th
    • Bugs stomped:
      • entering of registration code in very old installations is fixed

  • Version 1.3 April 2nd
    • New features:
      • Conversions for length, area, volume, mass, temperature, speed, fuel, pressure
    • Bugs stomped:
      • Changing to a floating point from programming mode would restrict the maximum number of digits that you can enter - fixed
      • Hex mode now really accepts upper case letters!!!

  • Version 1.2 March 19th
    • New features:
      • Obeys international locale decimal point and thousands separator e.g. 1,000.2345 can be displayed as 1.000,2345
    • Bugs stomped:
      • a change to programming mode with large abs(x) would cause an abort - fixed
      • A bad argument to ARCSIN would bomb the program. Fixed.
      • Hex mode now accepts upper case letters.

  • Version 1.1 March 14th
    • New features:
      • y u i o l ! ~ < > keys added
      • 'steal' Calc key added
      • factorials in real modes are now done in floating point numbers - you can now calculate up to 170! in reals (but accuracy is still limited to about 15 decimal places) and 12! in integer modes.
    • bugs stomped:
      • If the number of decimal places were set to 0 then you were not able to set to non-zero. Fixed.
      • error in Int & Frc fixed

  • Version 1.00 first release

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This page last updated on Mon Dec 23 10:33:38 EST 2002
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