Hi - I'm hoping to use the prune channels function in Homer3 but I'm not sure the best values to use.
I want to exclude channels if the magnitude of the signal is greater than 98% or less than 2% of the total range for longer than 5 s during the recording. Any tips on what values to enter for the prune channel function?
These numbers may change from system to system. (For the techen system ideal values would be 10^4 to 10^7 for instance). Similar SNR threshold can be used across systems, a value of 5 should get rid of most of the noisy channels.
I would like to use prune channels and in the videos it is said that you only use dRange if you have the appropriate system such as Techen and if not then you should set it to 0 and work with the SNR threshold. When I do that, I get an error message (error at line 95: Index exceeds matrix dimensions) and it doesn't work. Can someone help me there? Kind regards
There is usually more to the error message than "Index exceeds matrix dimensions" Error at line 95.
It should report the file name and/or function name. Odds are that this is an error that is arising in the hmrR_PruneChannels function. I looked at line 95 in that function which is
lst2 = find(dmean(lst)>dRange(1) & dmean(lst)<dRange(2) & (dmean(lst)./dstd(lst))>SNRthresh & rhoSD>=SDrange(1) & rhoSD<=SDrange(2));
I suspect you are getting the error because dRange and/or SDrange don't have two elements each. These are the user supplied parameters for the intensity range in the data which must have two values, a min and a max, and for the source detector distance range, again must have a min and a max.
Can you show us the parameters you used for this function? I suspect you didn't provide the min and max.
I'll note that we have on our to do list to check to see if the user has not provided proper inputs for the functions and to warn them of that in a user friendly way.