Bezier Approximation To Normal Curve


I hope everyone had an enjoyable Labor Day holiday (at least if you live in the US).  So far, everything is on track for a more formal announcement of my current project around the end of Sept. or early October.  In the mean time, here is a sneak preview.

The following diagram shows a normal distribution with zero mean and a std. deviation of 0.3 in red.  A quadratic Bezier approximation to the normal is drawn in white.  In general, for a very wide range of std. dev. values, the approximation can be computed over an arbitrary interval, [a,b] with no more than six quads.


While modern computers and devices are powerful enough to plot the curve point-to-point, the fast quad. Bezier approximation makes it very easy not only to redraw, but animate sections under the curve.  It is also very easy to apply line decorators to the drawing and plot all or part of the interval with dashed or dotted lines.

You also get the typical normal distribution functions that you would expect from Excel, including norminv (this one works fast and reliably, unlike traditional Excel).  And, this does not even represent one percent of the capability in the new library.

More to come around the middle of the Texas State Fair, so stay tuned and thanks for your emails.

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