extrema / News: Recent posts

v4.4.5 - now for linux as well as windows

- The contour plot feature has been completely rewritten. It now produces plots corresponding to the interactive help documentation (which was also updated).
- A graph legend should no longer disappear on a hardcopy or a window resize after setting LEGENDON false or using the DEFAULTS command.

Posted by Joe Chuma 2010-06-22

v 4.4.4

A bug was fixed in the calculation of the world and monitor coordinate systems after a change in aspect ratio. This led to a better result in PostScript output of text strings. Note: if you are having problems with Greek characters or other math symbols, copy the symbol.ttf font file from the fonts/ subdirectory to /usr/share/fonts/extrema.

Posted by Joe Chuma 2010-03-08

v 4.4.3

A 3D graphing speed button has been added to the visualization window which allows the user to plot (x,y,z) data on basic graph axes, with the ability to zoom in/out and rotate in 3 dimensions. The figure drawing speed button on the visualization window has been enabled which allows the user to interactively draw various types of arrows, polygons, and ellipses.

Posted by Joe Chuma 2010-02-05

v 4.4.2

The entire Help file structure was modified, reorganized and simplified (and corrected in some cases). The default location where the Help and Images directories are installed was rationalized to be /usr/local/share. A problem with autoscaling only one graph axis while the other is fixed has been corrected. The Windows version had a problem with reading a matrix from a file. This has been fixed.

Posted by Joe Chuma 2009-12-03

v 4.4.1

PostScript output of graphs with an automatic graph legend were not producing all the proper line widths. This should now be fixed.

Posted by Joe Chuma 2009-10-05

v 4.4.0

It's been a while, but a new version of extrema is finally released.

The parameter errors displayed on the resultant graph of the FIT gui are now set to the usual standard error (E1) instead of the reduced standard error (E2).

Added new general characteristics: BACKGROUNDCOLOR and BACKGROUNDFILE. The background of a graphics subwindow can now be set to a solid color or to a png image. Use SET BACKGROUNDCOLOR to set the background color for the current graphics subwindow (as chosen with the WINDOW command). Use SET BACKGROUNDFILE to set the background to a png image. ... read more

Posted by Joe Chuma 2009-09-27

v 4.3.6

The cursor is now positioned at the end of the command line on a command line recall with the up/down arrow keys.

Initial indexing for linear interpolation was off by one causing incorrect results in some cases. This is fixed.

New feature: import an image using the "import a drawing" button or the "File->import" menu item on the Visualization Window, then click the "Digitize" button on the Import Window to be able to digitize coordinates from the image and store the x-y values in vectors. For example, this allows the user to scan a graph from a journal article, producing a png or jpeg, and then digitize values from that image.

Posted by Joe Chuma 2008-05-29

v 4.3.5

The REPLOT command was failing for some cases of XLOGBASE or YLOGBASE > 1. This is fixed.

The GRAPH command was failing if autoscaling was on and a linear axis was drawn first, with a large maximum value, and then the logbase was set > 1 and the GRAPH drawn again. This is fixed.

Setting the virtual min/max was not working properly when the number of large increments was set to zero. This is fixed.... read more

Posted by Joe Chuma 2008-02-01

v 4.3.4

The FIT command was failing when the fit expression was an evaluatable text string, e.g., FIT y=EVALUATE(f) or FIT y=1*f, where f is a text string. This has been fixed.

Also, the Windows version of 4.3.3 had debug output which I forgot to turn off. This has been corrected.

Posted by Joe Chuma 2008-01-11

v 4.3.3

The REPLOT command was failing with the axis min > max. This has been fixed.

When reading data from a file into vectors, a record in the data file which begins with the comment character, default value '!', will be ignored.

The explanation of expression variables in the Introduction in the Help has been updated with more accurate information.

Posted by Joe Chuma 2008-01-08

v 4.3.2

Several source files were modified to accommodate gcc v4.3, which "cleaned up" some header dependencies.

Posted by Joe Chuma 2008-01-07



The GRAPH\POLAR and GRAPH\RADAR commands were modified. GRAPH\RADAR draws a polar plot with POLARAXISANGLE set to 90, POLARCLOCKWISE set to 1, POLARCOMPASSLABELS set to 1.

The help files were updated.

Posted by Joe Chuma 2007-11-30

v 4.3.0

Polar plots have been added. GRAPH\POLAR now draws a true polar plot. Polar plots have their own set of characteristics, and the help files have been updated with the new information.

The linux release was modified on 20 November 2007 to correct a small problem with the source file: src/Graphics/GRA_polarCurve.cpp

Posted by Joe Chuma 2007-11-19

v 4.2.10

When reading a matrix where the number of columns is not given, extrema was returning 1000 columns, which is obviously wrong. This has been fixed.

(linux version) All help files have been modified to remove extraneous Windows specific stuff and to fix up broken links and incorrect information.

Added trapezoid rule calculation to the INTEGRAL function. Syntax: INTEGRAL(x,y,'TRAPEZOID')

Posted by Joe Chuma 2007-11-01

v 4.2.9

You can now pass a script and parameters as command line arguments. This script will be executed immediately.

Linux example:
$ extrema --script "testIt.pcm 50 90 'some <alpha> string'"
will execute the script testIt.pcm with 3 parameters.

For the Windows version, you would have to open the properties for the extrema icon and modify the Target field.

Posted by Joe Chuma 2007-10-05

v 4.2.8

14/09/2007 Joe Chuma

The Heaviside function has been added.
HEAVISIDE(x) = 0.0 for x < 0, 0.5 for x = 0, 1.0 for x > 0

(linux only) The dependency on libxml2 has been removed. Extrema now uses wxXmlDocument and wxXmlNode instead.

(linux only) Modified Command, FCN_adev, FCN_mean, FCN_gmean, FCN_rms, FCN_skew, FCN_stdev, FCN_date, FCN_time, CMD_get, CMD_read, CMD_scalar, CMD_set, GRA_axis, ExSpinCtrlD, ExSpinCtrlI, and ExColorCtrl to comply with the gcc v4.1.x compiler.

Posted by Joe Chuma 2007-09-17

v 4.2.7

New context sensitive options. If you right-click on a graph legend, a form pops up allowing you to modify aspects of the legend, such as position, size, frame color, title color, title font, etc.

(linux only) New feature. A command line beginning with the % character will be interpreted as a system command, e.g., %ls. The output from the command is displayed in the terminal window.

Posted by Joe Chuma 2007-08-17

v 4.2.6

New context sensitive options. If you right-click on a drawn text string, a form pops up allowing you to modify aspects of the text string, such as color, height, angle, font, location, etc.

Writing a scalar to a file was failing with a complaint that it wasn't a vector. This has been fixed.

(Linux only) Writing a text string to a file was writing gibberish instead, due to a unicode confusion. This has been fixed.

Posted by Joe Chuma 2007-08-01

v 4.2.5

Replot with commensurate axes has been fixed.
New context sensitive options are available. Right click on a data curve on a graph, and a form pops up allowing you to modify the line type, line thickness, color, histogram type, plotsymbol type, color, size and angle, etc.

Posted by Joe Chuma 2007-07-30

v 4.2.4

New context sensitive options. If you right-click on the x- or y-axis of a graph, a form pops up allowing you to modify many axis characteristics, including color, location, scales, grid lines, tic marks, etc. This new feature will be extended to other graphical objects soon.

Posted by Joe Chuma 2007-07-10

v 4.2.3

06/06/2007 Joe Chuma


* (linux only) modified src/wxForms/VisualizationSpeedButtonPanel
Minor bug fix for PostScript output: if the .eps extension was not supplied, the plot file was created but not completed. If the .eps extension was supplied, everything was ok. This is now fixed.

* modified src/Commands/CMD_graph
Minor bug fix: if the legend is off and a string is supplied as the first argument to the GRAPH command, an error occurred. The string is now ignored, as specified in the documentation.

Posted by Joe Chuma 2007-06-06

v 4.2.2

04/06/2007 Joe Chuma


* New ELLIPSE command can be used to populate an ellipse given the major- and minor-axes, centre, and angle; or it can be used to fit an ellipse to a set of data points. The Help files have also been updated.

* New POLYGON command takes the coordinates for the vertices of a polygon and some data coordinates, and returns a vector indicating which
data points are inside/outside the polygon. The Help files have also been updated.

Posted by Joe Chuma 2007-06-05

v 4.2.1

(linux version only) Minor changes were made to the code to continue to allow linking with wxGTK v2.6.x. It is recommended that users upgrade to wxGTK v2.8.x as there have been improvements and the windows simply look better.

A minor bug fix was made to the aspect ratio section. Hidden pages were not being reset properly.

The commands ALIAS and DEALIAS have been implemented. ALIAS allows the user to create new commands out of the built-in commands. Command DEALIAS is used to remove an alias.

Posted by Joe Chuma 2007-05-16

v 4.2.0

PostScript output has been modified. Output files should be smaller and GhostView display of output files should be faster.

The Visualization window now allows for multiple graphics pages in a tabbed format. A new graphics page adds another tab. Use the new speed buttons to add a page or remove the last page. Also, you can use the new PAGE command to add or select a page.

Orientation (landscape/portrait) has been superseded by aspect ratio. You can still change the orientation, but you can also just change the aspect ratio (height divided by width of the graphics page).... read more

Posted by Joe Chuma 2007-05-08

v 4.1.10

The hyperbolic trig functions (sinh, cosh, tanh, sech, csch, coth, asinh, acosh, atanh, asech, acsch, acoth) were added.

A new PostScript driver has been written so the Greek characters and (most) math symbols appear properly in PostScript output.

Posted by Joe Chuma 2007-04-19