history.txt

A Cross-browser JavaScript DHTML Library which adds Drag Drop functionality and extended DHTML capab

! Dotted subgrid lines appear now also dotted when printed
--------------------------------------------------------------------------------
Version 0.86.3    (Release date: 30.9.2004)
+ Solving differential equations: Again increased precision (independendly from
  the order of the ODE), in "High Precision" mode 30% faster
! Integral dialog: Under certain though not very probable conditions,
  one or more of the function expressions within the dropdown list
  could be corrupt
--------------------------------------------------------------------------------
Version 0.86.2    (Release date: 23.9.2004)
+ Graphs can be drawn into the main window directly from the function calculator
  dialogs
! Zooming triggered by mousegestures wasn't correctly vertical-centered on the
  mousedown location
--------------------------------------------------------------------------------
Version 0.86.1    (Release date: 17.9.2004)
+ Small modifications of the appearance of the coordinate system
 (e.g. togglable border)
* Smarter detection of extrema at domain boundaries
! Vertical zooming didn't work if y min and y max were not user-specified
--------------------------------------------------------------------------------
Version 0.86      (Release date: 16.9.2004)
+ Can numerically solve up to fourth-order differential equations
+ 50% faster and strongly increased precision with solving third-order
  differential equations
--------------------------------------------------------------------------------
Version 0.85.2    (Release date: 8.9.2004)
* Subgrid not displayed by default
! When solving a differential equation, the application could crash in case of
  the solution being undefined at the basic value
  (example: y'=x/y with y(x0) having been set to 0.0)
! Wrong tooltips displayed on the dialog for differential equation input
--------------------------------------------------------------------------------
Version 0.85.1    (Release date: 7.9.2004)
* Several inconspicious improvements on the function calculator
--------------------------------------------------------------------------------
Version 0.85      (Release date: 2.9.2004)
+ Can numerically solve up to third-order differential equations
+ Solving second-order differential equations 40% faster and with increased
  precision
--------------------------------------------------------------------------------
Version 0.84        (Release date: 27.8.2004)
+ Integration: Now the starting point x0 of the integration interval is
  independent from the left boundary (x min) of the displayed x range
  => the integration can start anywhere inside (and to some degree even outside)
  of the visible range
+ Input textboxes for numbers (e.g. x min) now accept mathematical expressions,
  provided these follow the rules for function expressions, such as
  pi * -asinh(2.5*ln10) or, more realistically, pi/2
+ Factorial operator and function implemented
+ Enhanced WZG files format which now saves additionally...
  1.) ...with integrals, the lower limit (starting point) of the integration
      interval
  2.) ...with differential equations, the basic value, i.e. the data of the
      point through which the solution curve must pass
* Main grid lines slightly less accentuated, subgrid lines dashed
  => maingrid, subgrid, tickmarks and graphs should appear visually
  more distinct
--------------------------------------------------------------------------------
Version 0.83        (Release date: 17.8.2004)
+ Extended differential equation solving capabilities:
  Now the basic value (the point through which the solution curve must pass)
  can be placed arbitrarily between x min and x max - contrary to the earlier
  versions of WZ.Grapher which could only solve initial value problems
  with the basic value at x min
+ In the differential equation mode, now also normal functions (diff equs of
  the "zeroth order") can be entered. For example, y=x*sin(x) is as well
  accepted as y'=x*sin(y) or y''=xy*sin(y')
+ Input textboxes for numbers (e.g. x min, x max etc.) now accept also the
  predefined constants (PI, E, LN2 etc.)
--------------------------------------------------------------------------------
Version 0.82.2      (Release date: 15.8.2004)
+ Internal improvements on the differential equation solver engine (for example
  faster on first-order diff equs)
! On rare occasions the application crashed when being terminated
! Wrong integration results if the option "Absolute Integral" was selected
  (a bug regression from Version 0.82 on)
--------------------------------------------------------------------------------
Version 0.82.1      (Release date: 14.8.2004)
* Further memory usage optimizations
* Refinements on the coordinate system
- Some, in my opinion, useless backgroundcolor options removed
--------------------------------------------------------------------------------
Version 0.82        (Release date: 12.8.2004)
+ Function calculator can also evaluate a single value and it's derivative
  value
+ Function calculator: Increased precision near infinite derivative values
+ Context menu even for textedit boxes which are sensitive to mouse gestures
+ Smarter recognition of whether a file has been changed and needs to be saved
* Further inconspicious improvements
! Application crashed when a valuetable computation was started with the
  function expression textbox being empty
! Application could hang if the following three conditions coincided:
  1.) double buffered video mode switched off
  2.) the dialog for integration or differential equations was invoked the first
      time after application startup
  3.) the dialog was moved across the main window
--------------------------------------------------------------------------------
Version 0.81        (Release date: 7.8.2004)
+ frac() function implemented - returns the fractional part of it's argument
+ Can calculate negative numbers to powers whose inverse numbers are odd
  integers
+ Dropdown lists for function expressions now remember up to 20 functions
* Discontinuosities of a function are now also recognized next to x min and x max
  (e.g. with ceil(x) and x min being -5, no longer a vertical line is drawn
  at x min)
* Enhanced recognition of +-infinite derivative values when creating
  function value tables (e.g. sqrt(x) at x=0 or acos(x) at -1 and +1)
! Dialog for function definitions didn't remember it's previous height =>
  default height when re-opened
--------------------------------------------------------------------------------
Version 0.80.1        (Release date: 29.7.2004)
+ Improvements on managing the statusbar text
--------------------------------------------------------------------------------
Version 0.80          (Release date: 29.7.2004)
+ Can numerically solve differential equations  of the first and second order
+ Can generate function value tables, including the according derivative values.
  These tables can be straighly (buttonclick) copied to the clipboard
  and from there be pasted into Spreadsheet documents (Excel) etc.
+ The graph window, more precisely the coordinate system,
  can now be made quadratic (via Ctrl+Q or menu)
+ Accepts also a preceeding 'f(x)=' or 'y=' on function expressions. This
  should facilitate copying expressions from somewhere else into WZ.Grapher
+ The integral sign displays the bottom limit of the integration interval
* More toolbar buttons -> two toolbars instead of one
! The drop-down list for integrand function expressions was a bit stupid:
  It tended to remember erroneous function expressions too easily,
  and did not always insert the most recently used entries on top of the list.
  Moreover, it now can't anymore be fooled by whitespaces within expressions

  Despite the new features, the size of the application is still very small,
  just 189 kB, and memory usage is relatively frugal.
--------------------------------------------------------------------------------
Version 0.71          (Release date: 11.7.2004)
+ Dialog for integral input contains a drop-down selection list for
  integrand function expressions (remembers up to 15 functions)
! Application crashed when integration was started
  but the integrand input field was empty
--------------------------------------------------------------------------------
Version 0.70.3          (Release date: 9.7.2004)
+ Some minor modifications on the appearance of the coordinate system.
  Particularly, tickmarks can now be toggled independently from other settings,
  are also drawn on the top and right side, and their thickness is dependent
  from the linewidth setting
--------------------------------------------------------------------------------
Version 0.70.2          (Release date: 9.7.2004)
+ A few new minor additions, such as:
  The short guide that lists the helperfunctions and operators can also
  be called from the integral input dialog; 'Integration' in context menu
--------------------------------------------------------------------------------
Version 0.70.1          (Release date: 8.7.2004)
* Improvements of the integration engine (e.g. recognizes better limits of
  the integration interval, i.e. where the integral becomes undefined versus
  where the integrand is discontinuous but it's definite integral not undefined).
--------------------------------------------------------------------------------
Version 0.70            (Release date: 7.7.2004)
+ Numerical integration with high precision which accommodates automatically to
  screen resolution. Draws the integral curve.
--------------------------------------------------------------------------------
Version 0.62            (Release date: 29.6.2004)
+ Four different colour profiles (background colours) can be picked
* Again some performance tuning, some 5% faster
* Modifications of the code to be better prepared for planned
  future extensions (such as calculating integrals)
--------------------------------------------------------------------------------
Version 0.61.1          (Release date: 26.6.2004)
+ When the program starts, it displays an instruction how to enter functions
* A few modifications of the Help Topics and their rendering engine
--------------------------------------------------------------------------------
Version 0.61            (Release date: 26.6.2004)
+ Incomplete elliptic integrals of first and second kind implemented
+ Again slightly faster
--------------------------------------------------------------------------------
Version 0.60            (Release date: 25.6.2004)
+ Capable to print
+ Complete elliptic integrals of first and second kind implemented
+ Remembers last open/save directory independently from the Windows version
+ Subgrid visibility can be toggled
* Higher subgrid resolution, i.e. smaller subgrid divisions
* Extended automatic menu item disabling/enabling
* Improved color management on devices with less-than-24-bit color depth
--------------------------------------------------------------------------------
Version 0.55            (Release date: 5.6.2004)
+ The graph-picture can now be copied (either as scalable metafile or as bitmap)
  to the clipboard, and hence be pasted into other programs
  such as office suites (for instance OpenOffice, Word or Excel documents)
  or graphics programs (Corel etc.)
+ Can save preferences (to INI file)
* Many under-the-hood improvements, such as: The graphics mode switches
  automatically from doublebuffered to non-doublebuffered mode in case there's
  not enough videomemory available (too many instances or other
  programs open, particularly with maximized windows).
  Re-switches automatically to doublebuffered mode once memory is detected to
  be sufficient again
- Sound removed (I just felt so and might occasionally switch my mind again)
--------------------------------------------------------------------------------
Version 0.52            (Release date: 29.5.2004)
+ Gamma function implemented
--------------------------------------------------------------------------------
Version 0.51.1          (Release date: 29.5.2004)
* Improved recognition of earlier versions on the system
--------------------------------------------------------------------------------
Version 0.51            (Release date: 27.5.2004)
+ Now WZG files (WZ.Grapher files) are automatically associated
  with the program when it is started the first time
+ Additional command line option: Path of file to be loaded at startup
--------------------------------------------------------------------------------
Version 0.50            (Release date: 23.5.2004)
+ WZG file-type is now binary and saves the preferences which concern
  the look of the coordinate system and graphs
  (the new WZG type is NOT compatible with the previous text-mode one)
+ gaussd() function (Gaussian Bell Curve function) implemented
+ Bells and Whistles: Play sound when graphs are drawn :)
  (can be toggled via "Options" menu)
+ New exponentiation operator besides the already existing base^exponent,
  base"exp., base'exp. and p(base,exp.) supported: **, for example x**2
* Again about 25% faster
! Drag&Dropping a .WZG file on the application now brings the window
  automatically to the foreground
! The undocumented but nevertheless supported base