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The attached file contains of mobile positioning results of a person.
- How many days staid this individual in one place (did not move more than 1 km during 24 hours)?
- Name these places.
You can use Spatial Clusters
in the online calculator to solve this problem.
- Select method DBSCAN and have a look on demo data to learn how the data should be prepared. You have to form spatio-temporal clusters (option X Y DateTime). For this, the first column must contain a unique ID number. You should add it (in Excel). Date and time in the last column must be as a floating point number in Serial Date format used in Excel. The recorded time in source data can be converted to the serial Date format by adding the date in Excel Date format cell to time in a custom format cell ("h:mm:ss"). The sum should be formatted as a fractional number having three digit fractional part.
- According to the exercise, the clusters must contain temporally continuous records located within 1 km. The records have temporal interval 15 minutes — it means 95 records per 24 hours. Consequently, the Minimum number of objects in cluster must be 95. Search radius = 1000 (coordinates are in meters). Search extent along z dimension = 1 (the measurement unit in DateTime format is 24 hours).
- The number of clusters indicates the days stayed at a place, the location of clusters is visible in the output map. For viewing more precise location of clusters you should save the cluster centres and use their L-Est coordinates in Estonian geoportal. Open Tools → Location → National coordinate system. Input the seven-digit coordinate as X and the six-digit coordinate as Y.