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Everything posted by Simeon
Hi Melina, please make sure that there are no NA´s in the date: sum(is.na(data$Date)) If this is >0 than this is the fault and you need to remove these rows. Cheers, Simeon
Simeon replied to rorben's topic in Geolocator Discussion & Support's Geolocator Discussion & Supportmaybe without log-transformation?
Finally, an almost complete user`s guide for geolocator analyses. Check out the paper: https://besjournals.onlinelibrary.wiley.com/doi/10.1111/1365-2656.13036 As well as the online manual: https://geolocationmanual.vogelwarte.ch/ Lisovski_et_al-2019-JAnimEcol.pdf
Sorry - I am not sure what is happening.. are you working on a mac? If not try gr.Device = "default"
Hi Diane, have you plotted your light data to make sure that the threshold is within the range of measured light. And have you got any NA's in your time column (check for sum(is.na(raw$Date))). Simeon
Simeon replied to Melina's topic in Geolocator Discussion & Support's Geolocator Discussion & SupportThat is correct, median deviation for thresholdPath, since it ignores the error structure and zero devotion for the Estelle model. Running calibration during the equinox ist actually a good thing, if you have enough time around the equinox. Given the structure of errors around the equinox, estimates of latitude are very sensitive to zenith angles (sun elevation angles). Hope that helps, Simeon
Hi Devin If you intend to use FLightR, the rule of thumb are the following. Editing twilights: Only edit twilights if the automatic process has picked up a false sunrise/sunset (e.g. during the night) and when there is a clear twilight time in the morning or the evening. If you are unsure delete the sunrise/sunset time (press d). Deletion: It is best to delete sunrise/sunset times that are clearly heavily shaded, e.g. if the twilight event is much later than the surrounding twilights and the light either goes very quick to the maximum thereafter or is going up and down. FLightR is rather sensitive to false or heavily shaded twilight times/periods and the model with perform better and faster if such transitions are excluded. Hope that makes it more clear? Simeon
Hi, just a quick note: It is very important to choose a sensible threshold (slightly above the night values). If the threshold is too low, the function cannot define twilights and will kind of "crash" if it's to high you will have a higher effect of shading (at least if you are using any 'threshold method' to estimate locations. Regarding editing of twilights: 1) I would recommend to only edit twilights if the function has falsely identified a sunrise or a sunset time, e.g. sometimes there are small peaks of light during the night that exceed the threshold and are selected for a sunrise and sunset time. If you can see a clear twilight time at the right time (compare with previous and consecutive twilight the are shown in purple and green) that you can edit and move the twilight. If you are unsure leave it or delete it but don't make any guesses on where the twilight might have been. 2) It also depends on the method you will be using later on. If you use a curve method in SGAT or a template fit model in FLightR, the exact twilight time is not that important since it will only be use to extract the sunrise/sunset period. For an analysis with GeoLight or SAGT using the threshold method the twilight times matter a lot. However, and again, you subjectively alter you results if you make any guesses and edit twilight times to make the time series "look nicer". Cheers, Simeon
Hi, I am not sure what may cause the error - could be that there are too large caps in the time series of sunrise/sunset times (larger than the window)?! The output should be exactly the same as the output of e.g. preprocessLight but in case of deleted twilight times, the "Deleted" column is set to TRUE and in case of modified twilights, the "Twilight" column is the new data time and the "Twilight3" column the old datetime. Cheers, Simeon
Hi, The inserted twilights are new twilights and not "truly" edited twilights (changes in detected sunrise/sunset times), thus these columns need to be the same (they could be NA's for "Twilight3" but that would cause other problems). Most importantly, the column inserted shows that you have manually inserted these twilight times. Cheers, Simeon
Hi, It could indeed be that there are too many columns but most likely the columns have the same name. They need to be "Date" and "Light" (with capital 1st letter). Another issue could be, that the time format is not right. Best to see check str(Lig) and head(Lig) to see whether it all makes sense. ALSO, there is a package that is based on BAStag but has some further developments and bug fixes (e.g. TwGeos - github.com/slisovski/TwGeos). Cheers, Simeon