create_bmp_for_rect_in_rect
parrot /export/home/davek/atlc-2.02/src % create_bmp_for_rect_in_rect
Usage: create_bmp_for_rect_in_rect [-b bmp_size] [-f outfile] [-v] W H a b c d w h Er1 Er2 
where W, H, a, b, c, d, w, and h  are all in mm or all in inches
(they *must* use the same units. Non-integers allowed for all parameters)
options are:
  -b bmp_size
     Sets the size of the bitmap, the range 1 to 15 (default 3).
  -f outfile 
     Write output to 'outfile' instead of stdout
  -v         
     Write diagnostic information to stderr
-----------------------------------------------------------------------  ^
|                                                                     |  |
|               Dielectric, permittivity=Er1                          |  |
|                                                                     |  |
|       <----------------d------------------------->                  |  |
|                                                                     |  |
|             <----------w----------->                                |  |
|             ------------------------   ^                            |  |
|             |                      |   |                            |  |
|             |  Metallic conductor  |   |                            |  H
|<-----b----->|  conductor (can be   |   c                            |  |
|             |  off-centre)         |   |                            |  |
|             |                      |   |                            |  |
|       |------------------------------------------- ^                |  |
|       |..........................................| |                |  |
|       |.....Dielectric, permittivity=Er2.........| |                |  |
|<--a-->|.......(can be off centre )...............| h                |  |
|       |..........................................| |                |  |
|       |..........................................| |                |  |
-----------------------------------------------------------------------  v
<----------------------------------W--------------------------------->
***WARNING*** Since the output from create_bmp_for_rect_in_rect is binary data (the bitmap) it
will screw up your terminal unless you redirect the output to a file. The '-f' option can be used to send the output to 'outfile' 
parrot /export/home/davek/atlc-2.02/src % 
Here's an example of using create_bmp_for_rect_in_rect.
atlc and create_bmp_for_rect_in_rect) it is simply put on the command line, as is the vacuum (white region). 
create_bmp_for_rect_in_rect 61.5 20.13 5.1 22.5 0.5 50 15.0 5.0 1.0 2.1; test.bmpThe output was redirected to a file
test.bmp, which would then be read with atlc. 
% atlc test.bmpThat is all that needs to be done.
create_bmp_for_rect_in_rect must attempt to fit your dimensions to a square grid. If all dimensions are small integers, this is easy to do, but in some cases this is not possible without having very large grids. In this case, create_bmp_for_rect_in_rect can only generate an approximation of what you want. For example, assume a structure is 120x240.0001 mm wide. It's impossible to represent that on a square grid, without having a grid of at least 1200000 x 2400001, which would be prohibitively large and requre an enormous amount of time for atlc to analyse. In this case, create_bmp_for_rect_in_rect will approximate this structure. Here is a very approximate idea of the sizes of the bitmaps, and the time to analyse in atlc, for various values of b. 
| b | size (kb) | time (min:sec, for single 125 MHz CPU, Er1=Er2) | 
| 1 | 35 | 0:10 | 
| 2 | 74 | 0:38 | 
| 3 | 74 | 0:38 | 
| 4 | 195 | 3:59 | 
| 5 | 278 | |
% create_bmp_for_rect_in_rect -v 61.5 20.13 5.1 22.5 0.5 50 15.0 5.0 1.0 2.1 test.bmp User requested: WW=61.500000 HH=20.130000 a=5.100000 b=22.500000 c=0.500000 d=50.000000 w=15.000000 h=5.000000Er1=1.000000 Er2=2.100000 Internally the programme is using the following grid: W=492 H=161 a=41 b=180 c=4 d=400 w=120 h=40. The grid size is 0.125000 mm, inches or whatever This means we are simulating a transmission line with these dimensions: W=61.500000 H=20.125000 a=5.125000 b=22.500000 c=0.500000 d=50.000000 w=15.000000 h=5.000000 (mm, inches or whatever) These may be slightly different to what you indicated on the command line, but they are the best approximation possible, given the grid size parrot /export/home/davek/atlc-2.02/src %
atlc in a reasonable time. It's possible to reduce the size of the bitmap, so giving lower accuracy, but in less time, by setting b to 1 or 2, as like this.% create_bmp_for_rect_in_rect -b 1 61.5 20.13 5.1 22.5 0.5 50 15.0 5.0 1.0 2.1 test2.bmp % atlc test2.bmpor of course accuracy can be improved, by making b larger, as in:
% create_bmp_for_rect_in_rect -b 6 61.5 20.13 5.1 22.5 0.5 50 15.0 5.0 1.0 2.1 test3.bmp % atlc test3.bmp
atlc is written and supported by Dr. David Kirkby (G8WRB) It it issued under the GNU General Public License