Practical Manual - Malareo

ecords.
Switching and clearing your selection: Make sure that all the records are shown by clicking on
the first record, holding the SHIFT button, scrolling to the last record and clicking on it. Switch
your selection by clicking the Invert Selection button.
Basic statistics: Click on the Vector menu, then select Analysis Tools and then Basic Statistics.
Ensure your Input Vector Layer is Africa and the Target Field is POP_ CNTRY, then click OK.
What is the highest population of a country within Africa
What is the total number of countries within Africa
What is the Mean Population
Task 3: Querying data in attribute tables
Search: It is possible to select records in the table based on the values of particular attributes. If,
for example we wanted to know how many countries were landlocked, we would use the
“Search” function to do this. Type “Y” (note it is case sensitive) and in the drop down menu
select “Landlocked.” Then click on the Search button. You will notice at the top of the attribute
table that 15 records have been selected.
Advanced search: We are going to select the landlocked countries that use the Franc for
currency. To do this we are going to use the “Advanced search” function.
QGIS for Malaria Page 37