The correct way to average bearings is to the treat them as vectors, then average the x and y components separately before converting the resulting vector back to a bearing. It is likely this is what the trig functions mentioned in this thread are doing. Footleg On Fri, 18 May 2018 at 12:57, Bruce Mutton via Therion <therion@speleo.sk> wrote:

I agree to some extent with both sentiments below, however the software should not abort just because of backsight discrepancies.

What about adding one more line to the Therion and or Survex log file; either

“There are no backsights in the centreline”, or

“Maximum backsight discrepancy is xx [degrees|grads]”, as approprite

That way the user can be fully informed and make their own decision about whether to investigate further if the information is not what they expect.

Bruce

17. 5. 2018 v 9:25, Evaristo Quiroga via Therion <therion@speleo.sk>:

In this case is not a problem with my formula, is a serious magnetic anomaly (100 degrees difference) and the program should to stop and to send a warning.

Evaristo,

Therion is a program to interprete your data, not to solve problems with your data.

It is your responsibility what the data you import into Therion.

Martin S. _______________________________________________ Therion mailing list Therion@speleo.sk https://mailman.speleo.sk/listinfo/therion