The tag has no wiki summary.

learn more… | top users | synonyms

9
votes
5answers
288 views

Raster diff: how to check if images have identical values?

Is there a means to check to see if any 2 given raster layers have identical content? We have a problem on our corporate shared storage volume: it's now so big that it takes over 3 days to conduct a ...
5
votes
0answers
31 views

Graphically depict statistical difference between thematic rasters

The graph shows a regression between two raster datasets with classified tree canopy cover: class 1 = 0-10%, class 2 = 10 - 20% ...class 6 = >60% (Figure 1, Figure 2). The spatial resolution for ...
2
votes
1answer
30 views

How to subtract lines with thickness from polygon

I have a polygon and some lines crossing it. I want to subtract the lines with a certain "thickness" from the polygon, so it splits up into various polygons which do not touch each other anymore. You ...
3
votes
1answer
27 views

OpenLayers rules and context, what is the difference?

OpenLayers.Style employs two properties, "rule" and "context" which accordingly contain an array of OpenLayers.Rule and a set of methods. I have noticed that "context" can somehow substitute "rule". ...
3
votes
2answers
102 views

A python tool like GNU's diff for shapefiles?

I often use the GNU diff tool to compare two files or even two folders for differences. I was wondering if there is a Python based tool out there that does basically the same for shapefiles? In the ...
5
votes
1answer
212 views

Terminology problem - Raster vs Grid vs Lattice

I have a question about GIS terminology - what is the difference between grid and raster and grid and lattice - in theory?? I thought, that raster is regular network and value is in the cell and the ...
0
votes
1answer
125 views

Geographic Coordinate system and Projected coordinate system [duplicate]

Please Excuse me If I asked a Silly question : When to Set A Geographic coordinate system or projected coordinate system to a Shapefile?
2
votes
2answers
75 views

What is the difference between mosaicking and merging?

What is the difference betweem image Mosaicking and Merging?
4
votes
2answers
912 views

What is primary difference between ArcGIS for Desktop and ArcGIS for Server?

What is the primary difference between ArcGIS for Desktop and ArcGIS for Server?
7
votes
3answers
4k views

How to analyze differences between two shape files and put results into a new shape?

I have two polygon shape files of the same region from two different years (1985 and 1997) and I need to analyse the differences between the two shapes resulting in a third polygon shape file ...