Optimisation is the act of making things as good as possible with regard to some criterion, eg. more efficient, faster or slimmer.

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503 views

How to draw one rectangle in ArcObjects?

Is there button in ArcObjects "draw rectangle" such as in openlayers? Update Well, I use this code for drawing: ESRI.ArcGIS.Display.IScreenDisplay screenDisplay = Map1.ActiveView.ScreenDisplay; ...
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3answers
222 views

Looking for TSP with Target different from Source

I know the TSP (traveling sales person) in osm2po is beta but it works quite well. Is there a way to designate a final target location that is different from the initial source location. In other ...
2
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1answer
347 views

Find nearest neighbours faster in PostGIS

I currently have a query that calculates the number of useful amenities within a certain radius of each town, using OSM data: create table places as select town.name, place, town.way, ( select ...
2
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1answer
586 views

How to speed up this simple MySQL points in the box query

MySQL doesn't have nearest neighbor search so. So I try to come up with a "distance" that's reasonable so the number of returned query is around 20-200. That way innodb doesn't have to compute ...
2
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1answer
76 views

Maximize clusters of points from coordinate data

So I am definitely new to the GIS world, so bear with me if I don't know the best way to articulate my problem. That said, I am ready to learn, I would definitely welcome any direction that you all ...
2
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0answers
127 views

Covering a Polygon with Minimum number of circles with fixed locations

In QGIS, I have a vector polygon of a fixed size and shape. I also have a set of circles of a fixed radius and fixed location, which cover part of the polygon. What I would like to do is remove as ...
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1answer
88 views

Wind turbine placement optimization and loss on surrounding house value

I am doing a geostatistical placement optimization study on where would be the optimal placement of a wind turbine in a Danish region. One of the variables taken into account is the cost on the value ...
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1answer
505 views

Enhance performance of a join query for mapnik using postgis

I use mapnik to render map with datasources from a postgis database. One query is a join on two table, one with a geometry (a polygon) and the other one with some fields I want to use for rendering. ...
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0answers
24 views

How to make some constraint to be evaluated first in mysql?

SELECT BusinessID FROM tableauxiliary WHERE MBRContains( GeomFromText ( 'MULTIPOINT(-6.1928749092968 106.7651250907,-6.1771250907032 106.7808749093)' ), ...
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2answers
49 views

How can I optimize this point-linking query?

I have the following query, and am wondering how it could be optimised to run faster: WITH gps_nodes_1 AS ( SELECT "NODE_ID", "geog" FROM gps_nodes WHERE ST_Distance("geog",ST_GeogFromText('POINT( ...
0
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1answer
1k views

CQL Filter in Geoserver very slow?

I am experimenting with CQL filtering in Geoserver. I have two layers, one (A) has 8000 features, the other one (B) has 3000 features or so. I would like to search of layer A for intersection with ...
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1answer
35 views

Improving speed on pgRouting on table update with many rows: faster to loop on each row than a table update call?

I am updating thousands of rows in a survey table finding shortest path from each place a survey respondent visits. My code below is the query I use to update the blank route column. The function ...
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0answers
20 views

How to build an optimization model? [duplicate]

I want to make a model using QGIS. Is it possible? Then how can I develop a model. can anyone help me?
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0answers
82 views

I could use some help with a bit of code optimization

See edit below. I posted here a couple weeks ago looking for some advice on the best way to iterate through data. You can find that post here. I have since done some tweaking to the code, and ...