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8
votes
2answers
428 views

DEM Elevation Units

I'm fairly new to the GIS world, and have a quick question. I'm currently using 10.1. I do not know much about rasters, so does transforming a DEM from one projection to another automatically convert ...
7
votes
1answer
4k views

Understanding QGIS buffer tool units?

I have been trying to figure this out for a couple weeks now and have had no luck getting the buffer tool to accept anything but degrees as units of measure. I have found lots of stuff saying the ...
7
votes
5answers
2k views

Calculate distance in km to nearest points (given in lat/long) using ArcGIS

I have two point datasets in ArcGIS, both of which are given in WGS84 lat/lon co-ordinates and the points are spread across the whole world. I would like to find the nearest point in Dataset A to each ...
6
votes
2answers
1k views

What's the Workflow for buffering in meters/km using WGS84 layers?

I'm a little bit new to GIS, so bear with me a minute.... I'm using QGIS 1.7.4-Wroclaw and working with an SHP layer in WGS84. I want to buffer out to a certain number of kilometers from this layer ...
4
votes
1answer
439 views

How to specify coordinate reference system (CRS) for scalebar that is different to project CRS?

Is it possible to specify a coordinate reference system (CRS) for the scalebar that is different to the project CRS? For example, my project CRS uses geographic coordinates (lat/long), the reason ...
4
votes
1answer
749 views

Dimensional analysis/conversion problem: Map scale to image resolution (dpi)

Given a map scale of 1:17,200 and a raster whose cell size is 6 inches, what resolution (dots per inch) should I choose when exporting the map to an image in order to maintain the raster's native ...
3
votes
1answer
34 views

How can units be defined in QGIS for the Rasterize tool?

I am using QGIS 2.4 (Chugiak) via the kyngchaos build for OS-X. My question is--when using the Rasterize tool to convert a point vector layer to a raster and using the "Raster resolution in map units ...
2
votes
2answers
441 views

What is the unit the shapely length attribute?

I'm doing a very simple calculation of the length of a polyline using shapely: from shapely.geometry import LineString ... xy_list = [map(float,e) for e in xy_intm] line = LineString(xy_list) s = ...
2
votes
2answers
237 views

How do I know the vertical/horizontal units of my DEM? I'm creating a slope using gdaldem

I'm using gdaldem to create a slope map. I can apply a scale. The default is 1. The notes say: Ratio of vertical units to horizontal. If horizontal unit of source DEM is degrees (e.g WGS84 ...
2
votes
1answer
110 views

Label size in map units, geoserver .sld file

Is it possible to define labels in map units in a sld file? Thanks.
2
votes
1answer
135 views

Unable to change the layer unit in QGIS

I have been working with QGIS for 2 weeks and I got the hang of it now. The problem now is I cannot calculate the area of a created polygon. Because the layer unit is not changing to meters. When ...
2
votes
1answer
2k views

What are the units of the calculated area from a raster in decimal degree

I'm trying to calculate area for a raster file which contains 2 layers (0 for unsuitable habitat and 1 for suitable). It's been calculated successfully but I don't know what is the unit of the ...
2
votes
1answer
290 views

How to read the area column in QGIS?

I have few problems understanding how units are managed in QGIS. According to the area column I created for a shapefile, the area of a shape is 0.7727... I just checked on Wikipedia and indeed the ...
2
votes
1answer
1k views

How to get $length in meters in QGIS?

I read a lot of posts concerning that subject, nevertheless I cannot solve to problem of getting $length in the field calculator in meters rather than in decimal degress in QGIS. The CRS of original ...
2
votes
0answers
84 views

How do I set the composer layout units to inches?

I open an new composer and select ANSI A for my paper. The notation after the name is "Letter; 8.5inx11in", but the width and height are displayed in mm, and the units selection is grayed out, so I ...
1
vote
1answer
364 views

Pseudo-Mercator projection with Decimal Degrees?

Hope this isn't a duplicate, did some searching but none seemed quite the same. Projection I want: WGS84/Pseudo-mercator. Selected. Looks Great. Canvas units I want: Decimal Degress. Selected. ...
1
vote
1answer
175 views

Which horizontal unit is used on the table of the Profile Tool?

Does anyone knows what horizontal unit is used on the table of the "Profile Tool". Vertical is in meter but I don't know about the horizontal axis. Knowing the length of my profile, I tried to divide ...
1
vote
0answers
41 views

How can I obtain the unit of a projection SRID?

Given a projection SRID, is there a way I can obtain the coordinates unit string (meter, degree, ...) ? In PostGIS for example, it looks like it is present in the srtext column of spatial_ref_sys. ...
1
vote
0answers
443 views

Distance Matrix in QGIS

Can anyone help me with the distance matrix tool in QGIS? Is there a tutorial about it? It sometimes crashes when I use it and the values that it produces seem strange. I am a beginner in QGIS, so I ...
1
vote
0answers
61 views

QGIS scalebar shows a wrong scale [duplicate]

Possible Duplicate: Why does QGIS scalebar show a wrong scale? I want the scale-bar in QGIS to be in meters/kilometers. Usually it's in degrees, but if I change it to meters it is displayed ...
1
vote
0answers
577 views

mixing lon/lat and mercator layers in a MapServer .map file

I have a basic question about my MapServer .map file, which has two layers, each with a different coordinate system, longlat vs. mercator. See my .map file below. If I leave it as shown below, with ...
0
votes
0answers
17 views

Setting correct units for Near tool?

I need to use the near tool to calculate distances between data points and a stretch of coastline. My problem is that when I run the function, the values that come up in the Field of the points' ...
0
votes
0answers
17 views

Adding a Z Unit [duplicate]

I'm struggling with the Z Unit conversion of some data. Both the NHD data and my DEM are in a GCS with Decimal Degrees. These data sets project perfectly on the fly, but after I adjust the Z Unit of ...
0
votes
1answer
69 views

Adjusting Z Units on a DEM

I am learning how to use ArcHydro and attempting to change the Z Units because I get a warning message saying the Spatial Reference Doesn't Match. The DEM was in Meters, and I adjusted the Z Unit to ...
0
votes
0answers
92 views

changing unit of area from unknown unit to square meters

I am using Qgis 1.8 and I have this polygon.Now I wanted to know the area of this polygon and i have used field calculator and it shows my area as 651692439.under general tab crs is : EPSG:4326 - WGS ...
0
votes
0answers
71 views

change unit while outputting raster to ascii

I am having a problem with outputting ascii from raster file. I've reprojected and set map unit to meter in ArcMap. I've also set the output environment-ish parameters like output projection, x-y ...
0
votes
0answers
35 views

Scalebar unit different from project unit (QGIS) [duplicate]

I use QGIS 2.0.1 Dufour. My shapefiles and project is in that directory on Copy: https://copy.com/s7h6ZiiRJMXe All my shapefiles is in WGS 84, so.. the units is in degree. I want that units of ...
0
votes
0answers
191 views

How to change Editor Units to Feet for COGO Traverse?

I am in the Editing Options and looking for the place to change the Units to Feet from Decimal Degrees. I have tried going into my data frame properties and changing the display units to feet but that ...
0
votes
0answers
585 views

Convert a decimal degree to meters from the MySQL Spatial GLength

The MySQL Spatial function GLength returns the distance between two points, this distance is in the same unit from the projection. Since I'm using the WGS84 (SRID:4326) the answer will be with ...
0
votes
0answers
27 views

Set buffer radius in metric units in qGIS [duplicate]

Possible Duplicate: What is up with QGIS buffer tool units? A similar question to this one has already been asked QGIS - Change unit of measure from degrees to meters, but none of the steps ...