Thanks for the clarification. I admit to have missed the point, the test I made some time ago when starting using Therion were not enough accurate to show the vthreshold limit.
Marco On Thu, Nov 1, 2012 at 9:48 AM, Bruce <bruce at tomo.co.nz> wrote: > ** > > â¦so to clarify further â¦**** > > As the gradient of a survey shot increases, therion switches from the > assumption that passages are measured LRUD (vertical up down) to an > assumption that they are measured LR-front-back (up down perpendicular to > the passage orientation) and then at +-90 deg to the assumption that they > are measured NSEW.**** > > ** ** > > You can control the inclination at which the first change occurs by adding > **** > > ** ** > > vthreshold 40 degrees **** > > ** ** > > to your centerline block of data.**** > > ** ** > > Unfortunately we cannot change the NSEW behaviour (yet).**** > > What you need to know of course, is approach the surveyors took when they > were collecting the data, and adjust your input accordinly.**** > > ** ** > > Bruce**** > > ** ** > ------------------------------ > > *From:* therion-bounces at speleo.sk [mailto:therion-bounces at speleo.sk] *On > Behalf Of *Bruce > *Sent:* Thursday, 1 November 2012 7:08 a.m. > *To:* '**List for Therion users**' > *Subject:* Re: [Therion] Doubt about vertical sections**** > > ** ** > > Marco**** > > I tested your example and got the result you described with both xvi and > pdf outputs.**** > > ** ** > > I think you have found the transition defined by âvthresholdâ.**** > > From the Therion Bookâ¦**** > > â**** > > vthreshold <number> <units> â threshold for interpreting LRUD readings as > left-right-front-back reading perpendicular to the shot.**** > > If passeges are horizontal (inclination < vthreshold), LR is perpendicular > to the shot and UD is vertical.**** > > If passages are more or less vertical (inclination > vthreshold), even UD > becomes perpendicular to the shot â otherwise passages would not look very > good. In the case of vertical shots, UD is interpreted as north-south > dimension from the station to allow tube-like modelling of verticals**** > > â**** > > I had thought the default value of vthreshold was 60 degrees, but it seems > it may be around 67.5 degrees.**** > > ** ** > > Bruce**** > > ** ** > > ** ** > > _______________________________________________ > Therion mailing list > Therion at speleo.sk > http://mailman.speleo.sk/mailman/listinfo/therion > > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://mailman.speleo.sk/pipermail/therion/attachments/20121101/d6b99a79/attachment.html>
