Sorry, you have to do it from the beginning as the area of The Census
sub-place should be calculated as well.
The 4th step is something like:
area_of_intersection
number_of_unemployed * ----------------------------
area_of__The_Sensus_sub-place
Afterwards: Vector / Data Management Tool / Join attributes by location.
Remember to check "Take summary of intersecting features".
K.
Pretorius Deon - Lieutenant Colonel wrote:
Hi
1. Thanks for the assistance. I have done that up until your 3de
explanation point.
2. All the Sensus Sub Place data are now "cut" and within each policing district.
Perhaps any assistance on how I can now get the averages of each of the Sub Place
"numbers" per policing district.
Regards
Deon
-----Original Message-----
..
Just an idea:
1. Using the Field calculator add a new column with polygon areas for the
police district layer.
2. Create the third layer as an intersection between the Sensus sub-place layer
and the police district layer.
3. Using the Field calculator add a new column with polygon areas. Now you have
a attribute table to calculate the statistics.
..
Pretorius Deon - Lieutenant Colonel wrote:
..
I have a vector layer that exist out of about 1000 polygons of the
different police districts. Then I have a Sensus sub-place vector layer
with over 10 000 sub-places which indicate the number of unemployed
citizens per polygon. The Sensus sub-place layer therefor overlaps with
the police districts and when visualize some sub-places can make up 1%
up to 100% of a given police district. Most of the police districts
also contains 4 or more sub-places. The problem is I want to
calculate the "approximate" unemployment rate per police district by
using the data from the Sensus sub-place layer. Is there perhaps an
explanation on how I can determine" approximately proportionally" what
the unemployment is per police district. I am new to QGIS and not up
to date with programming, however any assistance would be appreciated.
..
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