0
votes
1answer
49 views

Determining direction of longest segment of polygon?

I have a shapefile with 9000 agriculture fields and what I like to do is to determine for each field (=each polygon) the direction of the longest segment. For instance, the selected polygon in the ...
0
votes
0answers
27 views

How to select duplicate polygons? [duplicate]

Although it may seem this has been answered before, there doesn't seem to be a solution. I am trying to simply select duplicate polygons. I don't want to delete them or anything like that. I need ...
3
votes
1answer
36 views

How to replicate the QGIS vector smoothing effect in ArcGIS?

You can see from the screenshots that QGIS has, in my opinion, much more pleasant on-screen rendering of vector features. I assume there is some sort of smoothing algorithm used in QGIS. Is there a ...
3
votes
1answer
61 views

Cropping or removing borders (not NoData) from multiple scanned and georeferenced maps (ArcMap or QGIS)

I have several hundred scanned maps in TIFF format, each correctly georeferenced and forming a large grid of images. The problem is that the border for each map is present - a white band, with a black ...
1
vote
1answer
54 views

Help choosing an appropriate GIS solution for the following question [closed]

I am currently researching for an appropriate GIS solution. My requirements are pretty simple: Ability to create circles, symbols or diagrams with transparancy tied to their geographical location ...
1
vote
1answer
84 views

Calculating the fractal dimension of a line segment

I have a shp file with hundreds of features that represent clipped segments of coastline. Each segment is made up of many vertices (dozens, perhaps even hundreds). (FYI, the segments were created by ...
1
vote
2answers
105 views

How to determine which polygons, if any, points fall within?

I am a amateur at GIS and need some help. I have a group of shapefiles of various areas and an Excel spreadsheet of addresses I have geocoded to points. I want to determine whether each point falls ...
2
votes
1answer
47 views

Display two-dimensional color gradient for two different quantities

I have two overlapping raster layers. One contains quantity A from 0 to 100, and the other contains quantity B from 0 to 100. I'd like to create a map displaying both sets of data at once based on a ...
1
vote
0answers
24 views

Automating polygon mergers with python

This is the first real world python program am trying to write. I am trying to create a scrip that takes a shapefile that has n polygons with an integer formatted date (e.g. yyyymmdd or 6/24/2014 is ...
0
votes
2answers
67 views

Any clue how to read a .style (ArcGIS) file in Python, for converting into another platform-specific format? [duplicate]

The problem I am face with is that I have all my data as shapefiles but my organization works with only 1 ArcGIS license. Migrating to QGIS to prominent amount of work, I need to convert my ArcGIS ...
1
vote
0answers
59 views

Selecting only parallel lines along a center line

Read through the previous post how to find close and parallel lines but still looking for a simpler solution. Found several ArcGIS forums post on the topic but no answers there either. It seems ...
0
votes
1answer
44 views

netcdf daily data to monthly raster layers

I have a netcdf (.nc) file of 95GB which consisted of daily data for a 50 years period. I tried to process this with ArcGIS (Multidimension tools – MakeNetCDFRasterLayer command) and it was not ...
1
vote
2answers
80 views

GIS Survey Line Plans

Has anyone ever heard of any tools in either Arcmap, QGIS, Mapwindow GIS etc, that could create a line plan (Survey Lines) across a polygon (Survey Area)? A form of input such as distance between ...
1
vote
0answers
92 views

QGIS 2.2.0 GRASS not worked

I use QGIS 2.2.0 on Windows 8 64 bit. I try to install use Standalone installer and OSGeo4W and still get the error And then i start GRASS C:\Program Files (x86)\GRASS 6.4.2>grass64 ╬╪╚┴╩└: ...
2
votes
1answer
48 views

Method for automatic aggregation of polys with sparse data

I am part of a project on presenting health related data on maps. In order to maximize the analytical usefulness of the data, we wish to divide them into as small areas as possible. However, to ...
1
vote
2answers
60 views

How to split a (road) buffer using the centerline?

I have a road centreline dataset which I have buffered using the road width. I used the standard QGIS buffer tool. I realise for my analysis I actually need to split the road buffer in half and ...
1
vote
3answers
34 views

Adding combined footage to points from the beginning of a line

I'm trying to add the footage of each point from the beginning of the line to the end. There are around 4k vertexes between the two ends that I need to put the footage from the beginning of the line ...
0
votes
0answers
39 views

Digitizing with OpenLayers Plugin seems incorrect

I am attempting to digitize some buildings based on floor plans using QGIS. To do this, I have taken the blueprints, georeferenced them against openlayers bing aerial plugin. I then digitized the ...
2
votes
0answers
36 views

Is there a “Disperse Markers” tool for QGIS?

I am using ArcGIS, but either I would like to use QGIS and maybe want to switch completely later. A have a point overlapping problem, as a result of geocoding of addresses. I have not found any ...
0
votes
2answers
62 views

Identifying clusters of points within a given distance

So I have a database of lats/longs representing incidents occurring on or near roadways. My goal is to identify the street block areas with the highest number of incidents in the database. I don't ...
1
vote
2answers
52 views

Create Shapefile of all overlapping features from single Shapefile

I need to create a Shapefile out of another Spahefile that consists all overlaps of features within the initial Shapefile. I'm sure there is a simple solution using ArcMap or QGIS, but at the moment ...
1
vote
2answers
68 views

User defined Coordinate Reference System (CRS) in QGIS is not located where expected?

I have received a shapefile with a user defined projection (i.e., +proj=krovak +lat_0=-32.923433 +lon_0=116.47485 +alpha=111.423433 +k=1.00004 +x_0=44328.529781 +y_0=1345943.211845 +ellps=GRS80 ...
1
vote
1answer
53 views

How can I open a .pmf file with QGIS?

I have spatial data that has been put together with ArcGIS and exported to me as a .pmf file. I'm spearheading a complete move from ArcGIS to QGIS and trying to make our old data still useful and able ...
0
votes
0answers
33 views

How to overlay polygons that are in the same layer

I need to INTERSECT many polygons that are in the same layer. Actually each polygons from my layer represent an area of influence from one specific bird species. Since I used to use ArcMap, I found ...
0
votes
1answer
47 views

Copy .prj file into QGIS projection folder

I want a custom projection used in ArcGIS be available in QGIS. I have the .prj file copied out of a ArcGIS folder (containing different projections). Now, I want this file to be added into QGIS. Is ...
0
votes
1answer
48 views

How to georeference a map - which is in projected coordinate system - using geographic lat long? [duplicate]

We have some hard copy maps which were projected in Gauss Kruger coordinate system (in the legend it has been mentioned). But, the coordinates were given in Geographic lat long (Beijing 1954). In ...
0
votes
2answers
62 views

Geo- referencing Projected coordinated raster with GCS - ArcGIS

I have raster displaying Lat/ Long grid, but map information shows that, it s been mapped in Gauss Krugger projetion/ Beijing 1954. So, technically we need to geo reference the map in Gauss Krugger/ ...
0
votes
0answers
38 views

Determining whether point location is left or right of line?

I have one line layer and one point layer. Points are located both sides of line. I want to know whether points are located on the right side or the left of the line. Is it possible to determine ...
1
vote
1answer
71 views

Finding left and right side of line in arcgis

i have road layer as line and polygon layer as building,i want to know left and right side of road in relation with buildings is it possible in Qgis or Arcgis?
0
votes
0answers
30 views

Determine Transect line to cover area

I'm near certain this is a solved problem, but I haven't been able to find a solution from searches so here's my situation (probably I'm searching the wrong thing)... I need to compute the ...
1
vote
2answers
35 views

Set border symbology by bordering feature?

I'm using a US state shapefile, and I want to have different border types based on properties specific to the border, not to any state. For example, I might want the Florida-Georgia border to be ...
0
votes
0answers
26 views

Cross platform gis api wrapper architecture

I have a python class library for arcpy which is just a couple of class definitions with my common code attached as methods and properties so that I can do code centralization for stuff that I have ...
0
votes
1answer
43 views

Mac QGIS files to Windows Arc GIS compatibility

If I download QGIS on to Mac will the shapefiles and layers I create be compatible with ESRI ArcGIS 10.1 on windows?
1
vote
0answers
75 views

How to get Drainage Divide and Streams from DTM

Does anyone know how you can get a map like this attached, having the digital terrain model? I'm sorry, but I do not know what is the exact technical term in English for them. I hope you understand ...
0
votes
1answer
54 views

In QGIS are there similare construction tools to ArcGIS?

For a project we are using ArcGIS to reshape autogenerated features. For that we often use the construction tools polygon, rectangel, circle, etc in ArcGIS. The right angle is also an often used tool. ...
2
votes
2answers
143 views

Convert from Julian Date to Calender Date in Field Calculator

Does anyone know of a way to convert from a Julian date to a regular calender date in either QGIS or ArcGIS field calculator? Thanks...
1
vote
1answer
37 views

How to export a IDW raster while keeping the search radius data

I want to export my IDW rasters that I made in ArcGIS to QGIS, however when I export my raster, the values are there but are no longer displayed. They are stored within each cell and are not ...
0
votes
0answers
55 views

Is it possible to apply affine transformation (translation) to raster image?

Is it possible to move/translate a raster image in QGIS 2.2 (without using georeferencer) just like it can be done with a shapefile ? If not, alternatively can this be done with ArcGis?
2
votes
1answer
39 views

How do I make this into a working CRS in ArcGIS?

+proj=tmerc +lat_0=0 +lon_0=-114 +k=0.9999 +x_0=0 +y_0=0 +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs I have this text string which I successfully used to project data in QGIS. How do I use ...
3
votes
1answer
88 views

Expand raster extent and set expanded values using nearest neighbor sampling

I have run a hydrodynamic model which has given me a grid of surface elevations throughout a bay. I am trying to process the results in ArcMap (or QGIS if needed). My goal is to take the current grid ...
0
votes
1answer
82 views

How do i create a flow line map for my data?

I am trying to illustrate a passenger travel flow map from a road terminal to several destinations on a road layer. I have QGis and ArcGIS, but I don't know much on how to start the work. I already ...
0
votes
1answer
78 views

Help in importing excel data

I have downloaded the hourly solar radiation data from NREL which is in CSV format but the problem is that the file does not have an exclusive column called latitude and longitude. There are 100s of ...
1
vote
1answer
131 views

Dissolve large dataset in ArcGIS and QGIS

I have more than 80k point data. I have created few buffer from 1 to 5 km of them. Now I want to get the covered area by 1 km to 5 km buffered range. For this I have tried to dissolve those individual ...
4
votes
3answers
128 views

How to shrink polygon on two sides?

I have a polygon which I know is a rectangle, although it may be at any orientation: I want to shrink this polygon by a third of the width from two sides, so that I just get the strip in the middle ...
1
vote
1answer
36 views

Overlay polygon on raster and save as new raster with same resolution

New to GIS and trying to learn. I'm trying to take a blue marble raster, overlay a countries .shp file, and save an image with the original blue marble image and the country outlines "burned into" the ...
1
vote
2answers
273 views

How to set Eclipse and PyDev for QGIS when ArcGIS is installed?

I have got a lot problems with the configuration of Eclipse with PyDev in order to develop QGIS plugins. The situation is very weird and frustrating. I can import qgis module using Pyscripter without ...
1
vote
1answer
101 views

problem reading netcdf

I am using qgis 2.2 (I have also tried this in qgis 2.0 and arcgis 10 with the same result) (I have some basic understanding of netcdf, but I am probably missing a lot of details...) I have manged to ...
2
votes
1answer
70 views

How to select only polygons that overlap with another layer?

I have two shapefile layers created from different thresholds from a predictive model (Pink=80; Yellow=95). Is there a way to create a new layer of only those pink polygons that contain yellow ...
2
votes
1answer
113 views

Calculating Topographic Exposure with Raster Calculator

I need you help trying to calculate Topographic Exposure (TOPEX) on a DEM in ArcGIS. I am trying to figure out wind exposure on a DEM with 25m cells. There is a great blog post where someone explains ...
0
votes
2answers
43 views

Erase within a feature class - Planar enforcement

I´m using ArcGIS v10 ArcInfo. I´m working with a feature class that has 5 features which are waterdepths (1 to 5m). These features are overlapping each other. What I need, is that they are not ...