Working with AttributesIn this exercise, you will focus on the attributes behind vector layers, and how they can be used to style, filter and label your data. Attributes for StylingGo to Layer > Add Layer > Vector Layer and add the wind_turbines_point.shp layer Right-click > Zoom to layer Right-click > Open Attribute Table, and have a look at the data Double-click on the layer, and in the Symbology tab, select Categorized from the dropdown at the top In the Value field, select STATUS from the dropdown Click Classify at the bottom of the dialog Click Apply to see the results The wind turbine points will be coloured according to their status To change the colours, double-click on the colour in the Symbol column Click OK to close the dialog Expand the wind_turbines_point layer in the Layers panel, and use the checkboxes to turn classes on and off
Attributes for LabellingUsing the same wind turbines layer you have been working on, double-click to open the Properties dialog again, and click the Labels tab In the dropdown at the top, select Single Labels In the Value field, choose an attribute to use as the label - for example STATUS or SITE_ADDRE Click Apply to see the results In the Labels dialog, try the options in the list of settings in the middle: Text: change Font, Style, Size Buffer: Draw text buffer to make the label stand out from background Background: Draw background to put a border round the label
When you are happy with the result, click OK to close the dialog
Filtering with AttributesRight-click > Filter on the wind turbines layer In the dialog, under Fields, double-click on YEAR Under Operators, click > (greater than) The Expression panel at the bottom will now read
"YEAR" > After the greater than symbol, type 2016 Click the Test button at the bottom of the dialog - this will show how many features are returned by the filter Click OK to apply the filter - only those features which meet the filter criteria will now be shown
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