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Public Domain Aeronautical Software (PDAS)  

This is a digital computer contouring program developed by combining desirable characteristics from several existing contouring programs. It can easily be adapted to many different research requirements. The overlaid structure of the program permits desired modifications to be made with ease.

The contouring program performs both the task of generating a depth matrix from either randomly or regularly spaced surface heights and the task of contouring the data. Each element of the depth matrix is computed as a weighted mean of heights predicted at an element by planes tangent to the surface at neighboring control points. Each contour line is determined by its intercepts with the sides of geometrical figures formed by connecting the various elements of the depth matrix with straight lines.

Although contour charts are usually thought of as being two-dimensional pictorial representations of topographic formations of land masses, they can also be useful in portraying data which are obtained during the course of research in various scientific disciplines and which would ordinarily be tabulated. Any set of data which can be referenced to a two-dimensional coordinate system can be graphically represented by this program. ( NASA Langley Research Center )

The italicized text above is from the official NASA release to COSMIC. If you would like to examine the source code for this program, you may download contour.zip and explore. There seems to be no documentation with this program. To date, I have hardly looked at this program. Maybe some of you have a greater interest. Most of the source code is Fortran, but a substantial amount is in CDC 6600 assembler. I would greatly appreciate any comments or suggestions.

PDAS home > Contents > In Progress > Contour
Public Domain Aeronautical Software (PDAS)