Arjen Markus

Just a short description of my professional activities and background (I felt obliged having participated on the newsgroup and the Wiki after several months):

• By education I am a physical engineer (a title not well known in Anglosaxon countries, but that is the translation from the Dutch).
• I have been working at WL | Delft Hydraulics for a good many years now, first as a project engineer working on water quality modelling, later on as a computer scientist (well, sort of), working on user-interfaces and tools for our consulting activities.
• I "discovered" Tcl/Tk when reading a famous book by Boris Beizer (BOOK Software Testing Techniques), and later on my attention was drawn to it again in connection to a testing tool (automated GUI testing). It was simply the tool I had been looking for. For all kinds of purposes: testing, manipulating files, boring stuff that I used to do with UNIX shell scripts or DOS batch files and so on.
• My interests: FORTRAN as a computational language, Tcl as a language for almost anything else and even a bit of numerics if I can manage it, testing techniques (although I should listen to my own advocacy at times :-).

Email: Arjen dot Markus At deltares dot nl

I have written several papers relating to Tcl:

• "Generating test programs using TestMake" - presented at the Second European Tcl/Tk User Meeting
• "Doing mathematics with Tcl" - presented at the Third European Tcl/Tk User Meeting
• "Combining FORTRAN and scripting languages" - published in the ACM FORTRAN Forum [L1 ], Volume 21, Number 3, December 2002.
• "Creative use of the text widget" - presented at the Fourth European Tcl/Tk User Meeting

Current mega pet project: The young programmers' project, intended to produce a booklet or book for young people or unexperienced adults to learn programming [L2 ]

Just to remind myself of the pages I have initiated (in desperate need of an update ...):

• A little business logic
• A little graphical pointer
• a little hail storm
• A poor mans GUI
• A simple memory game
• A simple GUI for decision trees
• A simple slideshow
• A simple version of Eliza
• A very short story
• Adding, multiplying and composing functions
• Agents, sprites and young programmers
• Angles and directions
• Automatic differentiation
• calling FORTRAN routines in a DLL
• Cellular automata
• Chatroom wisdom
• Clock and daylight saving time corrections
• Colouring graphs
• Combining FORTRAN and Tcl in one program
• Complex data structures
• Composing Curves
• Computers and real numbers
• Constructing curves
• Covering a four-dimensional grid
• Creating an animated display, part 2
• Creating an animated display
• Creating your own expr command
• Critcl goes FORTRAN
• Daddy, how does a computer work
• Dangerous constructs
• Differentiation and steepest-descent
• Dijkstra's guarded commands
• Discrete Fourier Transform
• Displaying tables
• Distributing a series of tasks
• Dutch Tcl Users Group
• exec and error information
• Experiments with matrix operations
• Fiddling with Fourier series
• finding the shortest paths in a graph
• Finite state machines
• Floating-point formatting
• Garbage collection
• Generating random strings
• Generating random tests
• Generic compiling and linking via build tools
• Genetic Algorithms
• Geometry
• Group theory and permutations
• GUI for an existing program
• How to make a Tcl application - part three
• How to make a Tcl application - part two
• How to make a Tcl application
• Ideas for a numerical analysis package
• Integral equations
• Looking at LISP's SERIES extension
• Managing FORTRAN programs
• Mandelbrot and Julia sets
• Manipulating infinite sets in Tcl
• Manipulating sets in Tcl
• Markov Matrices
• Mathematical workbench
• Moving dots
• Nested Radical Constant
• Non-ASCII characters
• On mathematical notation
• Parser using recursive descent
• Partial Differential Equations - performance benchmarks
• Pascal's triangle
• Passing arrays of data
• Performance of string reversing algorithms
• Physical empirical formulae
• Plots and charts
• Polynomial fitting
• Polynoms and power series
• Producing a fractal convex solid
• quality of source code
• Quick-n-dirty debugger
• Raster operations on the canvas
• Reading GIS shape files
• Recursive functions
• Robust environment variables on Windows
• Rough sets
• Setup of a Tk tutorial
• Simple data plotting example
• Simple method for computing mathematical limits
• Simple zooming and scaling in a canvas
• Simulating a server system
• Slicing arrays
• Small tool for the after command
• Splitting a string on arbitrary substrings
• Starkit with Iwidgets
• Strange figures
• Super-exponential growth in text manipulation
• Surreal numbers
• Taking the Nth power
• Three-dimensional shapes
• Traversing listboxes via the keyboard
• Vector spaces
• Writing PPM files
• Manipulating blocks of data
• FEMTOL
• Thinking about physical computations
• Viewer for functions of two variables
• Mathematical notebook
• Properties editor

AMG: Just a note. To delete a page, replace its entire contents with a single space. Obviously, feel free to delete this comment when you read it. AM ah, I had forgotten about that feature.