qgis training
TRANSCRIPT
Géoinformatique & Géocommunication
(10h Th, 20h labo, 80h proj)
TP n°1 (23/02/2016):QGIS
Pierre Stévens
Basic
Are you crazy?
Advanced
Intermediate
Trap
Best practice
Repeat
Don't do that
CTRL + N
CTRL + SHIFT + R
/bingHam/raster/srtm.tif
Check Layer Properties
CTRL + SHIFT + V
/bingHam/vector/utah_faults.shp
Check Layer Properties
CTRL + SHIFT + R
CTRL + SHIFT + V
Check properties
Play with style
Open attributes table
/bingHam/vector/utah_faults.shp
Vector =
Geometry + Attributes
Create a new field with the field calculator
The map unit is in degrees
/bingHam/vector/utah-faults.shp
This new field contains the length of the faults in kilometers
It is recommended to define
BBOX
Y minLat. min
X minLon. min
X maxLon. max
Y maxLat. max
bingHam/vector/bbox-bingham50km
EPSG:4267
EPSG:4267 EPSG:3857 EPSG:4326
raster.tiff vector.shp dem.tiff
Datasource projections
Project projection (EPSG:4267)
EPSG:4267 EPSG:3857 EPSG:4326
raster.tiff vector.shp dem.tiff
Datasource projections
Project projection (EPSG:4267)
EPSG:4267 EPSG:4267 EPSG:4267
raster.tiff vector.shp dem.tiff
Enable on the fly CRS transformation
Try several Projected Coordinate Systems
/bingHam/quarantine
/bingHam/vector /bingHam/raster /bingHam/tables
Sanitize
Transform
1) Clip this vector layer to your project extent
Right click → Save As
Vector → Geoprocessing Tools → Clip
/bingHam/quarantine/soilConservationZone4326.shp
/bingHam/vector/soilConservationZone.shp
2) Reproject it to your project CRS
1) Add vector and raster layers
2) Open attributes table and play with symbology
3) Add new attributes to an existing vector layer
4) Play with projections
5) Clip and reproject
What we've done
View → Decorations → Scale bar
Clip this raster layer to your project extent
Raster → Extraction → Clipper
/bingHam/raster/srtm.tif
/bingHam/raster/srtm_bbox50km.tif
/bingHam/raster/srtm_bbox50km.tif
Raster → Extraction → Contour
Raster → Analysis → DEM
/raster/relief.tif /raster/hillshade.tif /vector/contours.shp
For faster rendering, build pyramids on raster file
Properties → Pyramids
/bingHam/quarantine
/bingHam/vector /bingHam/raster /bingHam/tables
Sanitize
Transform
Compose a map
CTRL+Por Project → New Print Composer
Layout → Add mapLayout → Add scalebar
...