#!/usr/bin/octave -qH% -q causes Octave to run in 'quiet' mode, -H prevents the commands we use% from being added to Octave's command history.% function for converting a string which represents a binary number into a binary number% for speed we have no sanity checks. The number is read in the conventional sense (LSB on the RHS)function num = strbin (str)	num = 0;	len = max (size (str));		for i = 1:len		num = num + (str (i) - '0') * bitshift (1, len - i);	endendif (nargin < 1)	fprintf (stderr, 'Usage: bits2nec_nasa.m <code> <code> <code>...\n');	exit (-1);endmax_length = 1;n_wire_segments = 100;diameter = 0.002;displacement = 0.002;frequency = 150;for N = 0 : length (argv) - 1	code = sscanf (nth (argv, N + 1), '%s');	nbits = max (size (code));	if mod (nbits, 24) ~= 0		fprintf (stderr, 'Error: arguments must be a multiple of 24 bits (it is %i)\n', nbits);		exit (-1);	end	nsegments = nbits / 24;	FILE = fopen (sprintf ('/tmp/horiz_%i.nec', N), 'w');	fprintf (FILE, 'CM Automatically-generated NEC script (from bits2nec_nasa_fast.m)\n');	fprintf (FILE, 'CE\n');	prev_p = [0; 0; 2 * displacement];	for i = 0:nsegments - 1		length = strbin (substr (code, 1 + i * 24, 8));		if (length == 0)			length = 1;		end		theta = strbin (substr (code, 9 + i * 24, 8));		phi = strbin (substr (code, 17 + i * 24, 8));		p = [length * max_length / 256; 0; 0] + prev_p;% convert to radians			theta = theta * pi / 256;		phi = phi * 2 * pi / 256;% Generate coordinate transformation matrices (rotation about z and y axis)		tmatrix = [cos(theta), -sin(theta), 0; sin(theta), cos(theta), 0; 0, 0, 1]* [cos(phi), 0, sin(phi); 0 ,1, 0; -sin(phi), 0, cos(phi)];		p = tmatrix * p;			fprintf (FILE, 'GW %i %i %f %f %f %f %f %f %f\n', i + 1, n_wire_segments, prev_p (1), prev_p (2), prev_p (3), p(1), p(2), p(3), diameter);		prev_p = p;	end	fprintf (FILE, 'GW %i 3 0 0 0 0 0 %f %f\n', nsegments, 2 * displacement, diameter);	fprintf (FILE, 'GE\n');	for i = 1 : nsegments		fprintf (FILE, 'LD %i 1 0 0 3.767E+07\n', i);	end	fprintf (FILE, 'EX %i 3 1 0 100\n', nsegments);	fprintf (FILE, 'FR 0 1 0 0 %f\n', frequency);	fclose (FILE);	system (sprintf ('cp /tmp/horiz_%i.nec /tmp/vert_%i.nec', N, N));	FILE = fopen (sprintf ('/tmp/horiz_%i.nec', N), 'a');	fprintf (FILE, 'RP 0 1 360 0000 90 0 0 1\n');	fprintf (FILE, 'EN\n');	fclose (FILE);	FILE = fopen (sprintf ('/tmp/vert_%i.nec', N), 'a');	fprintf (FILE, 'RP 0 360 1 0000 0 0 1 0\n');	fprintf (FILE, 'EN\n');	fclose (FILE);end