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onlinegis [2020/10/21 11:39]
qcbs [Exercise 2 - Buffers and basic analyses]
onlinegis [2020/10/22 11:30] (current)
qcbs [Exercice 3 - Interpolation and raster manipulation with QGIS]
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 **Step 5**: Remove the shapefile layers and just keep the new layers from steps 2 and 4 to the canvas. Make sur the CRS of the canvas is NAD83 / Quebec Lambert.  ​ **Step 5**: Remove the shapefile layers and just keep the new layers from steps 2 and 4 to the canvas. Make sur the CRS of the canvas is NAD83 / Quebec Lambert.  ​
  
-**Step 6**: Add the (non-spatial) table '​BBS_Ovenbird_QC.csv'​ to the canvas using '​Layers>​Add Layer>​Add ​Vector ​Layer' and by choosing All files in the file types (yes, this is counterintuitive...)+**Step 6**: Add the (non-spatial) table '​BBS_Ovenbird_QC.csv'​ to the canvas using '​Layers>​Add Layer>​Add ​Delimited Text Layer' and specifying "No geometry" ​in the geometry options
  
-**Step 8**: From the menu 'Layer properties'​ of the layer '​BBS_Routes_QC',​ find the Joins tab, click on the (+) symbol and join the table BBS_Routes and BBS_Ovenbird_QC using the shared column '​Route'​ (select Route as both the source and the target columns). Disable the option to "Cache join layer in virtual ​memory"​. You should now see the number of ovenbird observations per year in the attribute table of the '​BBS_Routes_QC'​ file. +**Step 8**: From the menu 'Layer properties'​ of the layer '​BBS_Routes_QC',​ find the Joins tab, click on the (+) symbol and join the table BBS_Routes and BBS_Ovenbird_QC using the shared column '​Route'​ (select Route as both the source and the target columns). Disable the option to "Cache join layer in memory"​. You should now see the number of ovenbird observations per year in the attribute table of the '​BBS_Routes_QC'​ file. 
  
-**Step 9**: Activate the editing mode and use the 'Field Calculator'​ to add a new column (real, precision 2) to the table BBS_Routes containing the sum of the number of bird observations between 1980-1994 and 1995-2010. Each field has to be selected one by one from the Fields and Values list (sorry). Column names should have less than 10 characters, should start with a letter and should contain no spaces or special characters.+**Step 9**: Activate the editing mode and use the 'Field Calculator'​ to add a new column (real) to the table BBS_Routes containing the sum of the number of bird observations between 1980-1994 and 1995-2010. Each field has to be selected one by one from the Fields and Values list (sorry). Column names should have less than 10 characters, should start with a letter and should contain no spaces or special characters.
  
 **Step 10**: Save the changes and exit editing mode. Note that only the new columns that were created are really part of the BBS_Routes_QC table. Now remove the join (from the Properties menu) to remove the yearly observations. If you see a series of NULL values in the newly computed columns, close the attribute table and open it again. ​ **Step 10**: Save the changes and exit editing mode. Note that only the new columns that were created are really part of the BBS_Routes_QC table. Now remove the join (from the Properties menu) to remove the yearly observations. If you see a series of NULL values in the newly computed columns, close the attribute table and open it again. ​
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-**Step 12**: Use the Clip Raster by Mask Layer (under Raster>​Extraction) to remove the part of the Interpolated raster map you just created that falls outside of the boundaries of the province. Choose province.shp as the mask layer (make sure it's in the right CRS)+**Step 12**: Use the Clip Raster by Mask Layer (under Raster>​Extraction) to remove the part of the Interpolated raster map you just created that falls outside of the boundaries of the province. Choose ​the province ​of QC layer (from step 2) as the mask layer. ​
  
 Repeat Step 11-12 for the later (1995-2012) time period. Repeat Step 11-12 for the later (1995-2012) time period.