I have a set of points from a GPX file, and would like to create a heatmap from them, with the points weighted on the amount of time spent at that point.
I want to create a calculated field in QGIS, where duration will equal, either T-t where 'T' is the timestamp at the next point and 't' is the timestamp of the current point; or even better, (T-t)/2 + (t-s)/2 where 's' is the timestamp of the previous point.
However I'm unclear on how to bring values from other records into an expression.
أكثر...
I want to create a calculated field in QGIS, where duration will equal, either T-t where 'T' is the timestamp at the next point and 't' is the timestamp of the current point; or even better, (T-t)/2 + (t-s)/2 where 's' is the timestamp of the previous point.
However I'm unclear on how to bring values from other records into an expression.
أكثر...