0
votes
0answers
3 views

In which way is height information stored in a DEM?

I'm struggling with different DEM data, because I don't know how to convert the height information in meters. When I load ASTER and SRTM tifs in QGIS, it shows me the spectrum of the grayband (0 to ...
0
votes
0answers
8 views

Displaying multiple records with common zip code

I am uploading multiple records and want to use five digit zip code as the georeference. I would like to display each of those records on a map. Some of the records have identical zip code fields, ...
0
votes
1answer
10 views

Create a table with open() in a loop using the SearchCursor and InsertCursor

I like to create a table with open() in a loop using the SearchCursor and InsertCursor, but I don't know how. Before I used a few geoprocessing tools to get a field for percent. The Attributtable of ...
0
votes
1answer
11 views

How to batch-process attribute tables in QGIS (or GRASS)?

I'm using GRASS 6.4.3 in Linuxmint 16. I have a bash script for GRASS which I use to process almost 300 raster files. The script first imports some raster files (r.in.gdal), then does some ...
0
votes
1answer
8 views

How to add a new column into an attribute table in ArcGIS Online?

Is it possible to add a new column in the attribute table using the ArcGIS Online version or do I have to return to my home computer and do this through QGIS? A little background to help better ...
0
votes
0answers
4 views

Pyqgis 2.2 : How to allow editing on layer and features

I'm writing a pyqgis plugin with qgis 2.2 I succeeded in accessing and displaying vector data (geometries & attributes). Now I would like to allow editing for all my layers and all features ...
1
vote
0answers
14 views

How to clear spatial reference identifier?

I created a table in oracle with a sde.st_geometry column. I followed the instructions of ArcGIS help to register the table into geodatabase. My table creation statement is: create table ...
1
vote
0answers
14 views

Generalize lines with specific points

It's been a while since I was here. I have this problem now. I have electricity line feature class and point feature class intersecting line features. What I need to do is simplify this line feature ...
2
votes
2answers
14 views

Selection of lines that lays mostly in defined zone (majority overlap)

I have lines of surface runoff and I need to select the ones that are lying mostly in internal buffer of polygon. I'm trying to make some script in python, but it's very important to make the script ...
-3
votes
0answers
12 views

What is the best conversion tools?

I need to obtain a lot of base map in the following formats from a PostgreSQL DB: *.shp *.tab *.js (GEOJSON) I know that ogr2ogr is able to obtain these formats type. Do you know of other tools ...
1
vote
1answer
9 views

FME: How to retain Field names in reader?

I am having problems with field names in my writer using fme 2014. When I "generate" a workspace and pre-define the reader and writer before I add transformers, the readers field names are ...
-2
votes
0answers
13 views

Terminology Question [on hold]

I am looking for a general consensus about the use of of word or phrase. In a professional setting, do you think it is appropriate to ever use the word cartoon to describe someone else's work? I ...
1
vote
1answer
15 views

Zonal Statistics as Table Tool

I have a slope dataset. I have a polygon shapefile with territory within the extent of the slope map. I have to calculate the real surface area of this shapefile using the zonal statistics as table ...
0
votes
0answers
6 views

Configure Google Maps to display travel time by bike?

I move around by bicycle but didn't find how to configure Google Maps so that it displays travel time by bike: "x min ride home" would be more useful to me than "x min drive home" :-) Does GM ...
1
vote
0answers
11 views

geoserver wrong tile generation on leaflet

I am creating world map with bathymetry using Geoserver 2.5.1 and leaflet. It works perfactly upto certain zoom level. but after that i get few tiles drawn in wrong color as shows in images. Does ...
1
vote
0answers
19 views

QGIS: relative position of items in print composer

Is there any chance to make the items in print composer relative to the margins. Let's say for example the legend. I normally align it to the corner on the right bottom where the legend is 10 px away ...
1
vote
1answer
23 views

ArcMap Symbology: Assign Color by one attribute, symbol by other attribute

I've got a question concerning the symbology in ArcMap. I want to use the Unique values/Many fields option to assign unique values based on three attribute fields. To symbolize the first attribute ...
0
votes
0answers
13 views

How can I use regex in the AttributeCreator Advanced Editor in FME 2014?

I want to use regex to simply distinquish between POLYGON and MULTIPOLYGON using the regex term "\bPOLYGON" Apparently I can use the Advanced Editor and use ...
0
votes
0answers
13 views

Undefined symbol error when creating postgis extension

When trying to create postgis extension, I'm getting an error, no references in google on it. maptest=# CREATE EXTENSION postgis; ERROR: could not load library "/usr/pgsql-9.3/lib/rtpostgis-2.1.so": ...
1
vote
1answer
45 views

Calculating real surface area using Zonal Statistics as Table Tool?

I have a slope dataset. I have a polygon shapefile with territory within the extent of the slope map. how do I calculate the real surface area of this shapefile using the zonal statistics as table ...
1
vote
1answer
12 views

Profile curvature and soil moisture correlation: issue in interpretation

I have a question related to the profile curvature values. In an article I was reading (reference provided at the bottom of this question), scholars have found a negative correlation between profile ...
-3
votes
1answer
28 views

ArcGIS 10.2 home pc [on hold]

This Q has been asked before but it has been a couple of years since it has been answered. Is ArcGIS 11 going multi-thread? Can't get affirmative answer---other than background geoprocessing. So, ...
0
votes
0answers
9 views

Creating batch file from ERDAS IMAGINE Spatial Modeler?

How to create batch file from the ERDAS IMAGINE Spatial Modeler? I want to do the same process to different input images, something similar which we can do by batch processing of the existing ...
0
votes
0answers
12 views

How to remove ArcGISTiledMapServiceLayer completely

I have a problem related to "ArcGISTiledMapServiceLayer". I have an ArcGISTiledMapServiceLayer map service, which I have added to Map object. This service work as BaseMap. Now I want to add another ...
0
votes
1answer
8 views

Can I set individual scale levels for an ArcGISDynamicMapServiceLayer? [on hold]

I have a map service that contains 6 layers. I turned one layer into a feature layer. I used this layer in a query and show the result. I then would like to just show the other 5 layers as a ...
-2
votes
0answers
11 views

how can i obtain mean of 30 bands from the help of raster calculator in QGIS API with python? [on hold]

class BankAccount(object): def __init__(self, initial_balance=0): self.balance = initial_balance def deposit(self, amount): self.balance += amount def withdraw(self, ...
1
vote
0answers
31 views

How to create a rainfall raster from rainfall contours?

I downloaded a free rainfall data from the Philippine GIS Data Clearinghouse (PhilGIS) which are vector lines. How can I extract the data points from this? I want to extract it because i will be ...
0
votes
0answers
22 views

Converting DEM data to height information in meters using QGIS?

I'm relatively new with QGIS and currently I'm working with ASTER and SRTM DEMs. The goal is to create vector heightcontours with labeling in meter. Can you tell me how I can convert the grayband ...
1
vote
1answer
18 views

Efficient way to provide cached tiles? [on hold]

I am creating an app in Android that requires cached areas. I allow the user to cache an area of reasonable size. The server provides these tiles in a zip in the format /z/x/y.png. I took a (very) ...
1
vote
0answers
12 views

Clip Aerial Image Pair by Overlapping Area?

I have a set of aerial images which I am trying to clip by their overlapping areas, for use in a more involved program I am writing in Python with Python Imaging Library (PIL). Is there a command ...
0
votes
0answers
21 views

Raster Calculator

I have a slope dataset. How do I calculate the real surface area for this slope dataset using the raster calculator. This is the example I was given: orthogonal area of a raster cell in square ...
0
votes
0answers
23 views

Showing Google Maps using ArcObjects?

Do you know how we can show Google Maps as a base map in arcObject stand alone map? For example is there any wms address from google map that we can use it to connect to it or somthing like that? I ...
0
votes
0answers
21 views

How do I get polygon coordinates from shape files?

I have a shapefile that only has area and length data for the shapes, but I need to get the polygon coordinates. I've tried re-projecting with GDAL (at least I think that is what I did here) my ...
1
vote
0answers
16 views

Automatically generate & display distance to nearest polygon-feature? [on hold]

I´m working on data driven pages and I´m searching for a way to automatically generate and display the distance to the nearest polygon-feature in the map. It should be shown as a line from the ...
1
vote
0answers
17 views

How to sort a column in attribute table programmatically

Is there any way to sort ( alphabetically ) a column in the attribute table programmatically (without clicking on the column header) in QGIS ?
2
votes
0answers
31 views

Advantages of R-trees in comparison to geohashes

Geohashes are being widely used in products like: Lucene, mongodb, etc and have become one of the most important technology of present day. Have Geohashes replaced the good old R-trees or do R-trees ...
0
votes
0answers
25 views

Modifying properties of Attributes Table in QGIS?

In my QGIS project I'm using vector layers that require a lot of data inputting/editing. The problem is that some of the data I'm inputting varies greatly in matter of length and structure (various ...
1
vote
3answers
45 views

What is the opposite of height? [on hold]

Considering that depth denotes the distance below sea-level to a point on an object located below sea level, and considering that height denotes the distance to some point above the surface of the ...
0
votes
0answers
10 views

Creating a marker proportionally offset along a line in QGIS 2.4 when re-projecting

One of the nice new features in QGIS 2.4 is to be able to offset markers (e.g. arrow heads) along a line as part of the styling. I am trying to display a dataset of simple lines (not polylines) with ...
3
votes
1answer
22 views

Where i can find Mapbox tiles gallery

I'm sorry, if my question seems to be newbie, but i have discovered that cloudmade tiles service has been discontinued, so to switch to mapbox tiles, i imagine that i can find a gallery (like in ...
1
vote
1answer
19 views

Algorithm to find geohashes which satisfy query condition

I have an application where I need to query geohashes by specifying the bounding rectangle. Since geohashes map 2D to 1D is there a method by which I may find the prefixes of all geohashes which ...
0
votes
1answer
20 views

How to calculate Distance, Azimuth and Dip from two XYZ coordinates

I have two XYZ coordinates and I would like to calculate the Distance, Azimuth and Dip between them. I have come across a similar question on this site that calculates it the other way around (with ...
3
votes
2answers
140 views

Best Landsat-5 TM band combination for detecting fire scars

I am looking for the best band combination with Landsat 5 imagery to detect fire scars.
0
votes
0answers
7 views

Displaying a textbox on a certain point on map

Is there a way to display a label or textbox on a specific geo-place on a map produced by leaflet.js.? I know about the Marker- and Polygon Method But I can't find a way to put text in the polygon. I ...
0
votes
0answers
8 views

r.stream.* commands do not work in qgis environment

I have been working for a while with some grass commands in QGIS environment (r.watershed, r.terraflow, r.thin, r.to.vect etc) with out any problem. I haven't been able to get any results at all from ...
3
votes
1answer
71 views

PostGIS: Insert a Point using Python

What is the right way to insert a Point to a PostGIS database using Python?
1
vote
0answers
24 views

Use Ushahidi api in another map using openlayers

I have a ushahidi deployment and i am using Openlayers + ushahidi api to show the reports in a separate map along with other features. i have queried the data from ushahidi api and made a vector ...
3
votes
1answer
23 views

Wrong scale when importing dxf into QGIS

Has anyone had the problem that the scale of the shp layer converted originally from a .dxf file turns out to be wrong? (for example I draw a line of 10 meters long in AutoCAD and imported it in QGIS, ...
1
vote
1answer
32 views

Extract lat, lon Points from Polygon

I have PostGIS database, and want to extract lat, lon pairs sequence from Polygons (and MultiPolygons). As a very fresh PostGIS user, I'm able to just extract the Polygons: SELECT ...
1
vote
0answers
25 views

from shape files to a database

I've previously converted simple shape files to WKT so that I can store them in RDMS that has spatial capabilities. I'm a new user to QGIS, which I'm using to browse a shape file. But now I have a ...

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