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how do I use the -5 option of gendaymtx?

asked 2015-09-02 14:30:29 -0500

stephenwaz's avatar

when I enter:

gendaymtx -5 -m 6 -d -of my.wea > my.smx

program aborts and the standard usage message prints to stderr

when I instead try:

gendaymtx -5 -d -of my.wea > my.smx


gendaymtx -m 6 -5 -d -of my.wea > my.smx

the program seems to run fine, however examining the output shows non zero values for every bin that match the output of:

gendaymtx -m 6 -of my.wea > my.smx

if I run gendaymtx without the -5 option:

gendaymtx -m 6 -d -of my.wea > my.smx

I get the expected 0's in all but the 3 bins closest to the sun.

I'm running Mac OS Mavericks and I tried this with a gendaymtx compiled from HEAD in May as well as with the precompiled installer 5.0.a.4.


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answered 2015-09-02 17:27:20 -0500

updated 2015-09-02 18:34:06 -0500

The "-5" option to gendaymtx is there specifically for the 5-phase method, as you probably know, and isn't properly documented. Also undocumented was a recent change (last December) when an argument was added to this option for the angular subtense (diameter) of the solar disk, which was formerly fixed at 0.53 degrees. This was added to accommodate some anticipated need that escapes my memory, but Andy McNeil would know.

Your errors are all due to the command parsing being messed up because of the missing argument to -5. If you want the old behavior, use "-5 0.53", ugly as that is!

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Since the 5-phase tutorial is the only documentation for the gendaymtx '-5' option and it hasn't yet been updated, I have now added a little error-checking so a message will be printed when '-5' is missing its argument.

GregWard's avatar GregWard  ( 2015-09-02 17:53:36 -0500 )edit

I think we added the angular subtense to allow for the sun to be modeled larger to ensure that it appeared in small renderings when assessing glare. Either that or we wanted to use the 5-phase method in non-terrestrial settings.

Andyrew's avatar Andyrew  ( 2015-09-06 19:34:45 -0500 )edit

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Asked: 2015-09-02 14:30:29 -0500

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Last updated: Sep 02 '15