How to match isochrones with their related points?


#1

Hi,
First of all congratulations for your work, it helped me a lot. I’m new on working with geospatial data and I have a question abouth Isochrones. I ran OSM tools three times on QGIS for a bunch of points (1500 aprox.), because I need to get the isochrones for 5, 15 and 20 minutes using car. All ran without problems, considering the time between block of queries. The problem that I found is that I don´t know how to match the isochrones with their respective points. I thought into run an spacial join but they ovelrap, my second option is to create isochrones of 1 min walking to do the spatial join and get the indicator of my points but I don’t know the rules that OSM Tools uses to determine what isochrone is calculated first and also if OSM Tools run using the same order every time. Can you give me any tip to join the isochrones with their respective point?


#2

See here:

So far, it’s the feature ID, which doesn’t help you a lot. It’s in your isochrone file though. Before you start with 1500 isochrones again, use the field calculator to get a field with ID of your original (assuming you didn’t do ANY geoprocessing on that layer ever since, bcs that can alter the feature IDs) and join the isochrones FTID field on that:


#3

Thanks, it worked well.