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Kharita Challenges

Problems

Real geospatial problems, graded automatically. Choose a track, a level and what you want to hand in.

2 of 59 problems

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Track
Spatial Analysis1 problemPostGIS / SQL1 problemPython1 problemRemote Sensing0 problemsCartography2 problemsWeb GIS6 problemsData Management0 problemsGIS Architecture2 problems
Level
Beginner1 problemIntermediate1 problemAdvanced0 problemsExpert0 problems
Hand in
SQL0 problemsPython0 problemsGeoJSON0 problemsAnswers2 problemsSchema0 problemsDecisions0 problemsDataset file0 problems
Category
Data preparation1 problemData quality1 problemSpatial analysis1 problemRaster analysis0 problemsCartography5 problemsDecision support6 problemsGeospatial systems0 problemsWeb delivery2 problems
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CartographyWeb deliveryClear all
  1. Not started, How many tiles does an offline London need?Web deliveryAnswers

    From a bounding box to a tile count: size the offline basemap for a field app across zoom 10–15.

    Web GISbeginnerDifficulty: beginner140 XP~25 min3 checks

    You hand in your answers as values.

    Dataset

    • London boroughs · Polygon · 33 features · EPSG:4326

    What you’ll do

    • Take the bounding box of the borough layer
    • Convert box corners to tile coordinates at each zoom
    • Count tiles per zoom and total them into a storage estimate
    XYZ tilesWeb Mercatorofflinecapacity planningLondonAlso trains Cartography
    Open problem
  2. Not started, At which zoom does every capital get its own tile?Web deliveryAnswers

    Count capitals per XYZ tile across zooms to decide where a label layer switches from clustering to one label per city.

    Web GISintermediateDifficulty: intermediate180 XP~25 min4 checks

    You hand in your answers as values.

    Dataset

    • Populated places · Point · 1,251 features · EPSG:4326

    What you’ll do

    • Convert points to tile indices at several zooms
    • Find the busiest tile per zoom
    • Choose a switch-over zoom from the data
    XYZ tileslabelsclusteringzoom levelsglobalAlso trains Cartography
    Open problem