Here are some useful or entertaining Visual Basic creations, all fairly minimalist stand alone Windows applications...

GaussSmooth.exe Smooths and optionally resamples a 1D data series by interpolating the supplied data to resampled points using a local parabolic fit to the data in a Gaussian-weighted window.

RealFFT.exe Fourier transforms a time series data set using a Gaussian window applied to the data, and padding to a power of two. The normalization is such that isolatd peak heights (rather than areas) reflect the amplitudes of corresponding sinusoidal components. A simple peak finding graphic interface is also implemented.

dataclip.exe Picks out chosen columns from fixed-width data tables. Useful for rapidly extracting desired data from larger database files.

soundlog.exe This monitoring program reads the sound card mic input, Fourier transforms blocks of data, and graphs, vs. time, either frequency or amplitude associated with any dominant peak within a specified range. Double-clicking on the graph brings up a window for editing parameters.

2DNA.exe This program implements a simple DNA-like algorithm that takes strings of turning commands like "RSSLRS" and implements them on a 2D square grid. Turning left (L), right (R), or not turning (S) within each un-traveled square cell, or proceeding in the forced direction in already visited cells, results in a complex, tangled curve. These structures are shapes that can be closed if the curve returns to the original cell, or periodically duplicating otherwise. Thus, simple command sequences encode complex structures -- a DNA-like encoding.

vanderpol.exe This generates the continuous phase space plot of the driven van der Pol oscillator using 4th order Runga Kutta integration. It allows easy on-the-fly changing of the simulation and plot parameters, and various file output options for capturing variable time series. The scaled dynamical system is

v′ = -u + γ⋅v⋅(1-v^{2}) + δ⋅cos(Φ) |
u′ = v | Φ′ = ω |

with v the voltage, u the current, and Φ the drive phase of an LC circuit with a cubic-limited negative resistance gain.

Double-click on the plot to bring up the parameter control window.

PTvdP.exe Same as above, but a PT-symmetric dimer with PT balanced gain-loss conductances that include a cubic nonlinearity.

g1_g2.exe Same, but with individually adjustable left and right linear conductances combined with fixed cubic dissipative nonlinearities.

mazegen.exe This generates mazes by randomly filling in line segments of a rectangular grid. Chosen segments are rejected if they close off any section of the graph, and the filling continues until there are no remaining un-tested segments. The resulting maze is random, with only one path connecting any two cells.

Other interesting creations...

This Sun Chart presents the analema for Middletown, CT with rise, set, and transit data for times and positions of the sun graphically displayed.

This chart shows the climate for the area, based on forty years of climate data from Meriden Markham Municipal Airport (KMMK).

Please contact me, fellis@wesleyan.edu , if you want more details (or VB code) for any of these diversions.