Process only subsurveys in cavern and aven

[Eric C. Landgraf]

general notion: it should be possible to process subsurveys from a file. e.g. cavern --survey surveyname would only process that named survey (and anything it contains). This would allow processing of structured survex data as if it were split into multiple files, but allowing more freedom in how files are structured, is useful in identifying lengths of segments (especially when a survex file may not be processable on it's own due to disjoint segments)

This would also be potentially useful in implementing loop-closure tools.

[Olly Betts]

Tools which use 3d files already support this (via the img library which supports importing a named subsurvey). With survexport you can specify multiple subsurveys, and aven supports that via the UI but not currently on the command line (we should fix that).

I don't think this really makes sense in cavern though - you really need to process everything together anyway to handle the case of disjoint segments you mention. Also if you don't process everything together you can end up with different station positions when loops cross into surveys outside the named one.

So when you say "only process that named survey", you presumably actually mean "only write out that named survey to the 3d file". That seems better achieved by processing the whole thing to a master 3d file and applying the restriction when viewing/using the processed data, as is already supported.

As of two days ago, you can also now create a separate .3d file for a named survey (or surveys) via survexport --3d (also in aven's File->Export).

So this is really "wontfix" I'm afraid.