Survex (and therion) source formats

Graham Mullan graham.mullan at
Tue Aug 23 08:56:46 BST 2016

Having missed the first private exchange between Olly & Wookey, I might be a
bit behind the curve here, and I'm only mildly computer literate compared to
the most of you.

I'm unsure as to the full ramifications of what a 'namespace' is but can see
a difference between 1 at survey_1 and survey_1.1 to my untutored mind the
latter is a survey station and the former points to a survey station which,
in the raw data, is survey_1.1 Am I right?

Having been tutored by Andrew in both Survex and Therion for the best part
of 20 years now, I of course will agree with his analysis of how to build
and store data. I will make one comment about converting everything into
Therion - and I have done a lot of that - Survex is more flexible in that if
you miss out one column, usually the inclination one in the data we have,
then Survex doesn't notice. Therion does, which means one has to drop in a
column of zeros which was not in the data as originally collected. That is
not 'good practice' in my book as the raw data typed in should be exactly
what was collected, no more, no less. I have then forced the data to give an
approximation of depth using fixed points. Therion is perfectly happy to
accept imported .3d files that have been fudged in this manner. One day we
might get some caves resurveyed to modern standards but I don't have the
time or energy to deal with the many kilometres of cave this applies to.

What would be ideal is for both programs to accept the same raw data files.
If this is not possible, practical or preferred then Andrew's suggestion to
get Therion to 

import file.svx

Would be useful, though one wonders about the bits of the file that don't
apply to the centreline such as "Team" and "Copyright" I have no idea
whether these are processed in the same way by both programs. Would this be
possible given my worry, above, about missing data, though?

Above all, please whatever you do, make it backwards compatible somehow. I
have spent a hell of a long time typing in hundreds of legacy data files and
I really don't want to have to do it all again.


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