nnalg(1NCARG)

✨ nnalg — bestie edition ✨

okay so real quick, the manual name is nnalg(1NCARG) and it lives under NCAR GRAPHICS 💖 welcome to the Natgrid algorithm show-and-tell, she's iconic, she's niche, she's literally the coolest.

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🎀 NAME 🎀

nnalg — a lil tool for displaying features of the Natgrid algorithm 🦋

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🌸 SYNOPSIS 🌸

nnalg algorithmic_data_file

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💅 DESCRIPTION 💅

okay so nnalg takes a single argument, and that argument is the name of a very special file. not just any file, bestie — this one gets created by the Fortran subroutine NATGRIDS or the C function c_natgrids in the Natgrid package 👑

and what's inside it? data that's appropriate for displaying various features of the Natgrid algorithm. that's the whole vibe ✨

🚨 important: by default, this file is NOT created. like, it does not exist until you make it exist. to get it, you gotta set the parameter adf in the Natgrid package. and if you're feeling extra 💅 you can also override the default file name of nnalg.dat by using the parameter alg. yes queen, customize your life.

to invoke nnalg, simply type the command:

nnalg data_file

and then — the fun part — by editing the data file, you have many options as to what is displayed and what the appearance of the plot looks like. it's giving build-your-own-adventure but for graphs 🎨

the features that can be displayed are:

1. The input data points
2. The natural neighbor circumcircles
3. The Delaunay triangulation, derived from the natural neighbor circumcircles
4. The Voronoi polygons
5. The first order natural neighbors of a given input point (or points)
6. The second order natural neighbors of a given input point (or points)

and the tea ☕: the first four items in the above list are displayed in the default case. so you get 1 through 4 for free, no edits required. slay.

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🫶 USAGE 🫶

what gets displayed by nnalg depends on values in the input data file, which can be changed by manual editing ✍️

like. you literally open the file, you change the numbers, you change the plot. that's it. that's the whole mechanic. no cap.

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👀 SEE ALSO 👀

• natgrid

complete documentation for nnalg is available at URL http://ngwww.ucar.edu/ngdoc/ng/ngmath/natgrid/algorithm.html — go read it, iykyk 📚

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💜 COPYRIGHT 💜

Copyright (C) 2000 University Corporation for Atmospheric Research

The use of this Software is governed by a License Agreement.

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and that's the whole page, bestie 🥰 this was nnalg(1NCARG) from the UNIX manual, dated March 1997-1998 — yes she's a vintage icon and she ate 💅✨ mwah, go plot something gorgeous 🌈🦋🎀