Re: Ideas on iOS GPS tracking needed

2020-11-10 Thread Graham Samuel via use-livecode
Just a little more info for those that are interested. In general, it is extremely frustrating having to recreate a solution to a problem which has clearly been solved already many times. I can list several iOS apps which I use personally that appear to give reasonably accurate measures of

Re: Ideas on iOS GPS tracking needed

2020-11-05 Thread Jimmieson, Phil via use-livecode
Hi Graham, PS The only test data I have been able to find for the XCode Simulator is a bike ride in California which runs along giving a succession of GPS . It is quite useful, but naturally it doesn’t involve anomalies. You can make your own location simulations to run in the iOS simulator.

Re: Ideas on iOS GPS tracking needed

2020-11-04 Thread Graham Samuel via use-livecode
Thanks Alan and Bob - I was beginning to think I was alone on this one… Yes, I do look at horizontal accuracy. I found out the following using my iPhone XS. 1. Horizontal accuracy tends to be rather poor for the first 10 to 20 readings after activation, typically 65 metres. In context, a test

Re: Ideas on iOS GPS tracking needed

2020-11-03 Thread Bob Sneidar via use-livecode
Seems to me if you are tracking linear movement, you need to average the trending values, say the last 5 or 10 reads, against a time base, and reject the ones outside an acceptable tolerance. You may reject some good data here and there, but something grossly outside tolerance should be pretty

Re: Ideas on iOS GPS tracking needed

2020-11-03 Thread Alan Stenhouse via use-livecode
Hi Graham Are you checking the horizontal accuracy of each reading? (It's part of the array of data with your lat-longs, as well as speed, etc - though not on every phone). If not, try that and see if the anomalous readings are hugely out. From my experience, that's normally the case. If so,