history.txt

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

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WZGrapher Function Grapher
File:   history.txt
        Updatelog of WZGrapher
Author: Walter Zorn
Web:    http://www.walterzorn.com
        http://www.walterzorn.de

Legend:
+ New feature
* Changed feature
- Removed feature
! Bugfix


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Version 0.95      (Release date: 4.11.2007)
! Fixed GDI leak under Windows 9x/ME. Could lead to a crash after frequent
  updates of the coordinatesystem.
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Version 0.94      (Release date: 6.11.2005)
Executable renamed from wz_grapher.exe to wzgrapher.exe
+ Supports graphs in polar coordinates, also for ordinary differential
  equations.
+ Mousegesture duration no longer infinite (now 1.5 seconds).
+ Detailed main help can now be invoked directly from function input dialogs
  (per F1 key).
+ Changes to axes titles can be applied immediately, while the dialog
  is still open.
+ Messagebox that requests confirmation if user changes default values
  for x- and y-range.
+ Up to 1024 scroll/zoom undo steps.
* Rendering of coordinatesystem is worlds faster, especially perceptible
  when also subgrid is displayed.
* Drawing the zoom selection rectangle is faster (perceptible on slower
  machines).
* Some improvements on the rendering modules for graphs and help windows.
* Improvements on the printing engine (e.g. leaves margins).
! Fixed: Parallel installed versions < 0.91 won't crash at startup anymore
  (this is actually a bug in those old versions, the new version just
  doesn't "uncover" it anymore).
! Regression: Results y of cot(x) were offset by -pi.
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Version 0.93      (Release date: 4.5.2005)
+ New: Derivative operator d(). Computes the derivative of the expression
  within the parentheses. Examples: y=d(x^2) or y=1/12*d(d(x^4)). Supported
  maximum nesting level is 3 (allows to compute up the 3. derivative).
+ Main dialogs and thus function input textedits can be resized horizontally.
  The app now remembers these sizes and positions also when being restarted.
+ Main and help window can be KDE-like dragged by simultaneously pressing the
  ALT key.
+ Accuracy of drawn integral solution curves further improved through
  pixel alignment of the lower integration limit.
+ Zoom functionality regards whether the concerned range (x or y) is displayed
  in units of PI.
- Select box "Draw 1. derivative" on the dialog for normal functions removed.
  The new derivative operator d() has made this option needless.
! Single-value-calculator bug from V. 0.92.7 was not yet properly fixed,
  did occasionally evaluate y' to false infinite.
! Fixed: Resizing the function input dialog vertically didn't work properly.
! When selecting a zooming rectangle, stretching the rectangle beyond the left
  window boundary didn't work correctly.
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Version 0.92.9    (Release date: 15.4.2005)
Parts of core code rewritten, e.g. the coordinate system engine and the
functions for formatting and drawing numbers.
+ Draws now also sub-tickmarks.
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Version 0.92.8    (Release date: 24.3.2005)
+ Graph image copied to clipboard via CTRL+C is now also GIMP-compatible.
  Consider that in GIMP you cannot paste external data from the clipboard via
  CTRL+V; use "Edit"->"Paste From Clipboard" instead.
+ Mousecoordinates-tooltip can display values in units of Pi.
! Fixed: Selecting a zooming rectangle with the mouse could not be canceled
  by pressing [Esc].
! Bug introduced with v 0.92.7: Single-value function calculator did not always
  print the first derivative value and could occasionally crash.
- Zoom functionality of help windows disabled (didn't work properly with some
  video cards - I'll try to fix that later).
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Version 0.92.7    (Release date: 20.3.2005)
+ Draws optionally also the 1. derivative, of normal functions as well as of
  ordinary differential equations.
+ ODE-solving function calculator: Inserts initial values into the value tables
  when these are copied to the clipboard.
+ Supports XP styles (themes) when running on Windows XP.
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Version 0.92.6    (Release date: 6.3.2005)
+ Improved file name handling, e.g. filename is now set to "untitled.wzg"
  if not yet userspecified.
! Fixed: Out-of-bounds memory reading could occur with binary files corrupted
  in a certain manner (missing zero-bytes in ascii section of file).
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Version 0.92.5    (Release date: 28.2.2005)
* Coordinates at mousepointer displayed also while selecting a zoom rectangle.
* Zoom selection rectangle entirely visible also when expanded beyond the app's
  window boundaries.
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Version 0.92.4    (Release date: 25.2.2005)
+ Can be run from Startmenu/Execute
  (via command wz_grapher.exe, optionally with WZG file as parameter)
* Function calculators for both normal functions and differential equations
  in same tabbed dialog.
* Context menus for function-input dropdownboxes.
* Improved memory management, again slightly less memory usage.
! Occasionally false singularity recognitions when rendering functions which
  are difficult to graph, such as sin(1/x).
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Version 0.92.3    (Release date: 11.2.2005)
+ Helperfunction sqr( ) squares argument.
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Version 0.92.2    (Release date: 9.2.2005)
! Fixed: Crash if multiple instances were running and the function input dialog
  of another instance was open when WZ.Grapher was closed.
! Bug regression from v.0.92 fixed: GDI leak when axes titles were displayed.
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Version 0.92.1    (Release date: 9.2.2005)
* Numerical integration: Improved handling of incontinuousities if lower
  integration limit x0 is less than x min, i.e. outside of displayed x range.
* Slightly faster rendering speed when displaying integrals.
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Version 0.92      (Release date: 5.2.2005)
+ Coordinatesystem either crossed or boxed style. Tickmark labels can be toggled
  independently from the coordinatesystem style.
+ Titles for axes user-renameable. Axes titles are also saved to WZG files.
! Black background was printed in grey.
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Version 0.91.6    (Release date: 28.1.2005)
+ Enhanced contrast of visualized integral area.
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Version 0.91.5    (Release date: 26.1.2005)
+ Can save graph images as GIF (up until now as BMP only).
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Version 0.91.1    (Release date: 16.1.2005)
! Crashed on WinXP when started the first time after installation from a
  useraccount without admin rights.
! Function parser didn't recognize as syntax error the second argument of a
  two-arguments helperfunction being displaced into a following one-argument
  function.
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Version 0.91      (Release date: 10.1.2005)
+ "Undo" functionality for zoom and scroll actions, with up to 200 undo steps.
  Also, the "Undo" menu entry classifies the type of action
  (e.g. "Undo: Scroll").
+ Mousewheel support: Help windows - scroll; main window - zoom in, zoom out
  centered on position of mouse cursor.
+ Text of help windows can be zoomed in and out via menu or keyboard.
+ The "Save File?" messagebox that comes up when the application is about to be
  terminated can now be disabled.
+ Option to reset all preferences and settings
  ("Options"->"Reset All Settings").
* Behaviour of zooming by vertical mouse gesture changed: now zooming is
  centered on position of the cursor (same behaviour as with zooming by
  mousewheel), rather than moving the point underneath the cursor to the window
  center.
- Command line option for initial window size removed (WZ.Grapher remembers
  last window size instead).
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Version 0.90.1    (Release date: 28.12.2004)
+ gamma() function: increased precision, particularly with arguments
  less than 1.0.
+ Toolbar button to toggle visibility of coordinate system border
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Version 0.90      (Release date: 21.12.2004)
+ WZ.Grapher now remembers mathematical expressions filled into inputs for
  numerical values (x min etc.). Up until now, WZ.Grapher 'forgot' these
  expressions and showed their decimalpoint equivalents when a dialog came
  up again.
+ Changed file format which remembers the above mentioned expressions for
  numerical inputs.
+ Can now calculate both in radians and degrees angular mode.
+ Improved syntax error handling of input expressions, such as:
  Now the user is notified when he uses a comma instead of a period as
  decimal point. Earlier versions just ignored the digits after the comma,
  such truncating the number to integer.
+ When terminated, WZ.Grapher saves the current user settings (to INI file)
  and re-uses them when being started the next time.
Iconspicious improvements, such as:
+ Default x and y range values can be altered from within input dialogs.
+ Number of running instances of WZ.Grapher can optionally be limited to one.
+ When going to be closed, WZ.Grapher now asks the user whether other running
  instances should also be terminated.
! Under Win 9x, when an expression syntax error was detected, the concerned
  input dialog box was occasionally dublicated.
! Could under some circumstances be crashed by zooming via keybord while
  the mouse was on a toolbar button with the button's tooltip being displayed
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Version 0.88.2    (Release date: 1.12.2004)
+ Coordinate system grid, ticks and labels can be displayed in units of Pi
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Version 0.88.1    (Release date: 5.11.2004)
+ Content of Help windows can now be printed
* Enhanced stack protection
* Several internal optimizations
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Version 0.88      (Release date: 19.10.2004)
+ Improved file handling: Now the surfaces for functions, integrals and
  differential equations each can load, display and handle files independently
  from each other
+ When displaying an integral curve, WZ.Grapher now visualizes the
  integration area below the integrand by filling it with light-blue
+ First experiments to provide import capabilities for files from other graphing
  programs: Can import Equation Grapher (.EGR) files
* Minor modifications on how the coordinate system is displayed
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Version 0.87.1    (Release date: 14.10.2004)
+ Differential equation (ODE): The basic value and hence the solution curve
  are now exactly pixel-aligned => again increased precision of the drawn graph
! Value table of ODE: Wrong results if the x0 of the basic value, as specified
  by the user, was not x-step-aligned, for example:
  wrong result if
  x min = -5.0, x max = 5.0, x step width = 0.5, x0 = 1.25 (not x-step-aligned).
  Yes, now the basic value may be placed anywhere between x min and x max,
  independently from the x step width
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Version 0.87      (Release date: 12.10.2004)
+ Can compute value tables of ordinary differential equations (ODE);
  like those for normal functions, these value tables contain also the
  first-derivative values
+ Can numerically solve up to fifth-order ODE
+ Numerical integration between 20% and 70% faster