Winplot for Windows 95/98/ME/2K/XP/Vista/7 (824K)
Responding to a pair of user reports, I found and fixed a couple of bugs, which mostly pertained to the 2D translation of graphs. There was also a crash-producing bug in the 2D Italian surface of revolution dialog box.
A Polish version is now available, thanks to Piotr Pawlikowski. At the request of a user, a standalone construction for indefinite integration has been added to the function library — “intv(f,a,b,n)” is the integral of f with respect to v, from v = a to v = b, where f, a, and b can be arbitrary expressions. The integration variable “v” can be changed to another letter. The optional integer parameter n is proportional to the number of subdivisions; its default value is 40. The derivative of the gamma function is now enabled, and the polygamma function psi(n,x) of order n has been added to the function library. Two branches of the Lambert W function have also been added — lamb(0,x) and lamb(–1,x).
At the request of a user, field vectors in 2D and 3D can now be displayed with varying lengths. The feature is activated in the edit dialog by enclosing length information in brackets (see the Equa help text). At the request of another user, optional image axes can be added when transforming a curve. A transformational error introduced in the previous update was also repaired.
The 2D parsed-domain feature introduced on 12 May 2010 was not being applied to transformed functions (rotated, reflected, translated) or to their derivatives. Now it is.
A user reported some anomalous behavior when he tried to insert 51 evaluated text items into one of his 2D diagrams. The bug has been found and removed.
A couple of amendments to the previous announcement. I forgot to construct the intersection region for files that had been saved with that display mode active. It is easy enough for the user to click “intersect” to do this, but now the program will do it automatically when it encounters such files (and will hide the rest of the list). I also forgot to instruct the new shading dialog box to warn the user about saving changes; that has been corrected.
A user requested that the 2D implicit shading dialog box allow the shading of more complicated regions. Now you can shade the intersection of any two items in the region inventory (which has accordingly become a multi-selection list box). A couple of repairs were also made to the displayed numerical scale. In particular, the partially visible “5” at the end of the default x-axis is gone. I await news of unintended consequences.
A user reported that the 2D extreme-value dialog was reporting incorrect values for r when tracing a polar curve. This bug seems to have been present for many months; the simple typo that caused it has been repaired. The About dialog has also been revised so that its contents can be selected and copied.
An interesting issue was raised by a user. I had forgotten that points, because they serve as anchors for supplementary text, must be updated when the diagram is animated in any way, even when the points themselves are hidden during the redrawing. A repair has been made.
Three issues to report. First of all, the File menu now maintains a list of the six most recently active files, and updates it whenever files are opened or saved. (Initially this list will be empty, of course.) This is new territory for me, so I have my fingers crossed. This feature requires one of the two substitute versions if you are using Vista. Second, a user remarked that the effect of checking the item “Misc|Colors|Graph In Black” has been changed. Indeed it has (a few months ago). The menu item now does exactly what its name says, replacing all current plotting colors by black; uncheck the item and the color is restored. As for the original meaning of the item (to make black the default graphing color), that capability now exists in an expanded form; to declare a plot color as the default for subsequent examples, simply leave the color-selection window open as you exit the curve-editing dialog. The third reason for this update is to correct the confusing, inaccurate presentation of nth-order differential equations, which appeared in January. My original plan was to use my newly devised syntax “derx(n,f(x))” for derivatives, but that turned out to be rather tricky to program, because “f(x)” has to refer to an unknown function. I thus adopted a simpler way of referring to an unknown function and its derivatives, namely the Newtonian “xdot(n)” — a system that implies “t” is the independent variable. I forgot to modify the text descriptions of this system, however. Although the feature has worked all along, the dialog box and help text suggested otherwise! Repairs have been made.
A long-time user pointed out a subtle but egregious bug in the Inventory dialog — pressing Enter occasionally closed it (when more than one item was selected). Pressing Enter should not have done anything, and now it does not.
One of those unintended consequences was just reported to me. A bit of carelessness on my part caused the dotted-mode feature of 24 July to collide with the placement of arrows on parametric curves. Should be ok now.
A couple of minor additions to report. At some time in the recent past, a user requested that the default pen thickness be adjustable. My solution was to let the user change it by entering the desired thickness with an “@” suffix. This is a belated announcement of that feature. Another user wanted to disable the View|Connected property for selected graphs (instead of all at once). This is now done by entering the pen thickness with a “?” suffix. The View|Connected menu item has accordingly disappeared.
Thanks to a user request, displayed equations can now be managed like other supplementary text — their color, size, and placement are individually adjustable. I await news of unintended consequences.
To my consternation, I discovered that the “Paste script” item in the Misc menu was not handling user-defined functions properly (except for the first one, they were being ignored). The feature works again. Sorry for any inconvenience.
Another user report and request has been processed. The IVP dialog box is now displaying text-based formulas for initial conditions, as it should have been. The hailstone function “hail” has been added to the Library of functions, so this is a new version.
A veteran user reported that slope fields were being displayed badly when the tick intervals on the 2D axes were markedly different. Indeed they were. I thought that this issue was resolved long ago, but it needed fixing. My fingers are crossed.
There has been a flurry of helpful user feedback recently, mostly about nuances; for instance: the numerical scale has always been marked on the axes when the axes were drawn. Since the axes (and the grid) are part of the background, this has created occasional annoyances for those who care how the numerical scale interacts with the graphs. My attempts to manage these issues have never quite succeeded, so in this version the axis scale has finally been separated from the axes themselves, and put on top of the drawing (like any text overlay). For those who want to keep the scale in the background, the help text for the View|Grid dialog box explains how. I also fixed some glitches that were keeping SVG and EPS output from matching what is on the screen. I await news of unintended consequences.
A few bugs in the logarithmic windows have been fixed (implicit curves were not working, for one thing).
On-line help pages are now available.
A few weeks ago, I decided to hide the file extensions (wp2 and wp3) in window captions. To my surprise, a user informed me that these were actually useful to him. Now they can be turned on and off, using the “name” button in the Inventory — just de-select all inventory items and click the button.
The function constructor ifpos has been enhanced to allow more than one comma, as in ifpos(f|g,h|k,...,p|q,r). The value of this expression is f if g is positive, else it is h if k is positive, else ... else it is r.
Reinstated an appropriate default interval for 2D polar graphs, taught the initialization files to remember a few more user preferences, and fixed some wayward absolute-value signs in the inventory descriptions.
Improved the clipboard graphics functions (copy and paste), which were behaving erratically. Thanks to a veteran user for pointing out the irregularities. The Tip of the Day dialog is now initiated randomly (which I mistakenly thought was happening all along).
Integration in polar coordinates (r dr dt) has been to the 3D|One menu, and surfaces of the form z = f(r,t) now appear in the Surface Area dialog box. I do not know what took me so long to think of adding these items.
Differential equations of order greater than 2 can now be defined and their numerical solutions plotted. The new items are in the Equa and One menus of 2D windows. This capability has been requested a few times during the last fifteen years, and I finally decided to give it a try. Depending on the feedback, further developments may be forthcoming.
Early last September, I managed to disable the 3D View|Rotate|Z-axis Tour display. A user reported the breakdown, and it is now operational again.