SOFTWARE ANNOUNCEMENT - 15 February 1997
Future Skill Software (Herbert M Sauro)
I’ve just uploaded to the Oxford metabolic software archive a copy of a
small Windows (3.1 or 95) utility I’ve written called vExplorer. This
program allows users to enter mathematical functions (algebraic or
parametric) and interactively explorer their behaviour. Functions are
entered using normal mathematical notation. vExplorer always assumes
that the symbol ‘x’ is the independent variable in an algebraic
equation, and assumes ‘t’ is the parametric independent variable. All
other symbols are considered to be parameters, for example, ‘m’,
‘Slope’, ‘Vmax1’, ‘Banana’, etc. are all legal symbols.
For example, given the equation, ‘m*x + c’, vExplorer treats ‘x’ as the
independent variable (x-axis variable) and the ‘m’ and ‘c’ symbols as
parameters. The program will dynamically create two sliders on screen
corresponding to ‘m’ and ‘c’ so that the values of ‘m’ and ‘c’ can be
easily controlled by the user. The program then graphs the function. The
user can now change the sliders and observe the effect on screen. Once
you try it out you’ll soon realise what it’s about.
Metabolic Application
So what use is this program to metabolic people? The main interest here
is that vExplorer can also draw the 1 st derivative and/or the
elasticity of the given function, so it is now a trivial task to study
for example the effect of L, c and n parameters of the MWC model on the
substrate elasticity coefficient - and good fun it is too. vExplorer
will let you save functions to libraries for later retrieval and I’ve
included with the distribution a number of small libraries, there’s a
trig library, a polynomial library, power series library and to save you
typing (or remembering) the MWC model, a simple enzyme library.
There are other tools included with the program to help you manage the
graph, all under mouse control, panning, zooming, rectangular sections
etc. You will find that all operations occur in real-time so a
reasonable machine is recommended, at least a 486 66Mhz. A small help
file is included and most controls have hints attached to them so you
should find the program pretty easy to use.
Where to get it....
There are two ways to get hold of a copy:
By ftp from bmsdarwin.brookes.ac.uk/pub/software/ibmpc/explorer/setupve.
exe
By hyperlink from http://www.fssc.demon.co.uk/other/vexplorer
The setupve.exe file is a self-extracting/installing program, just
execute it.
I’ve noticed one mistake with the uploaded version which is that the
hint under the ‘Clear’ button in the function manager says ‘Delete
selected function’, this is incorrect, it should read, ‘Clear all
entries’! Something not mentioned in the docs: When vExplorer starts up
it tries to load a default library, called default.equ. If it can’t find
this file it loads an internal default. At the moment the default lib
contains some polynomial functions, however if you’d like the enzyme
library to load at start up just rename the enzyme lib, enzyme.equ to
default.equ.
There are certain restrictions on the use of vExplorer. If you wish to
play around with the program for a couple of weeks, or you’d like to
give a copy to your kid for his/her maths homework or you wish to use it
on an amateur basis, then be my guest. However, if you wish to use the
software in a professional capacity, i.e. as part of a course at a
School, College or University, or as part of your professional research,
or in a profit making business then you must obtain my consent. I have
no interest in subsidising professional organisations. Under no
circumstances may the software be sold separately or as part of a larger
package.
Have fun
Herbert Sauro
--
Herbert M Sauro
Future Skill Software
email: HSauro at fssc.demon.co.uk
Telephone: 01974 282428
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"He who cannot draw on 3000 years is living from hand to mouth" Goethe
"Ah, but a man's reach should exceed his grasp, or what's a heaven for?"
R Browning.
