lecture 5 Flashcards
what is a query
request to select feature records from database
what is a query in GIS
selection of data by attributes or location
what is attribute query asking
asking for the raw data from the query
what is spatial data query
making new data using query
what is spatial analysis
processing of examining the location attributes and relationship of feature in spatial da ara through overlay and other analytical techniques in order to address a question
example of spatial analysis (4)
local vs focal
spatial aggregation filtering
spatial analysis local what
per cell operation
what does focal spatial alteration allow
down sampling raster to make number of cell less higher to low
density in raster
count the number of incidence within radius
what do you control when calculating density in raster
resolution search radius (circle) shape of the neighbourhood
kernel density useful for
empirical model provides Way to visualise and quantify points of posters of hotspots were local density is high
spatial analysis vector clip what is it
overlay a polygon on one or more and extract feature cookie cutter
what does clip create
new geometry therefore is analysis
spatial analysis vector union what is it
adding one feature to another making a feature with different shape
what is union in spatial analysis vector
adding one feature to another making a feature with different shape
what does union create
new geometry example of analysis
spatial analysis vector reclassification what is it
renaming information to data w same value decrease amount of data overall
spatial analysis raster reclassification what is
reclassifying information in cells so its easier to digest
what does reclassification create
new attribute information
spatial analysis dissolve vector
removing boundaries that has same values
what does dissolve create
new geometry
spatial analysis vector buffer
select area around specific areas
what does buffer create
new polygon
what is network analysis
network consisting of vertices and edges
what can network analysis have
rules such as no turning right
what problems can network analysis solve
some for shortest paths most optimal parh
