A reference framework consisting of a set of points, lines, and/or surfaces, and a set of rules, used to define the positions of points in space in either two or three dimensions.

learn more… | top users | synonyms (3)

1
vote
0answers
96 views

Creating custom CRS for India toposheets using QGIS?

Indian toposheets (pre-2000 series) of 1:50k scale are in Polyconic projection, with Everest 1956 spheroid and India-nepal datum. How do I create a custom CRS in QGIS to represent this, so that I can ...
1
vote
0answers
41 views

How can I see the overlay of two features (point & polygon)?

I am trying to open two digitized layers, one containing points in a region and second which I have downloaded separately for the region as polygon layer. I would like to overlay two of these layers ...
1
vote
0answers
91 views

LIDAR Dataset displaying 500,000 meters to the East of correct position

First post on here.. I've been hung up for a couple days. Why does my LIDAR dataset show up ~500,000meters to the east of the correct position even though a spatial reference/coordinate system is ...
1
vote
0answers
71 views

LLA vs ECEF--which to choose?

I will be providing points in 3D to an external source via XML. One coworker suggests Lat/Long/Alt and another suggests ECEF. We can do either without much trouble. We have an existing product that ...
1
vote
0answers
107 views

Intersection between a ray from lat, lon, alt, with pan, tilt and earth's surface

I have a problem that consists of finding the intersection point between a ray from a given lat, lon, alt, that is looking to a given pan and tilt angles and the earth's surface. I need the lat, lon ...
1
vote
0answers
66 views

How does Arbitrary Coordinate System in QGIS work?

I have got the drill hole data, which needs to be geo-referenced based on non-earth coordinates system (with no datum, ellipsoid information defining through Custom CRS). Could any one explained me ...
1
vote
0answers
111 views

Converting custom grid to OS grid

I have two sets of data, one is in OS coords, no problem there, but the other was set out in about 50 off 10x10 metre grids aligned to a 'feature' on the ground. I do have the OS coordinates of their ...
1
vote
0answers
51 views

Gauss-Krueger coordinates in Openlayers

I want to show the coordinates of my map in gauss-krüger coordinates, but nothing works. I tried another projection, displayProjection, lonLat.transform but the answers are the same. my source ...
1
vote
0answers
105 views

Reference to Basemap instance's coordinate system

I use the matplotlib basemap toolkit (mpl_basemap.Basemap) to plot GeoTIFF images on a map background using pcolor() or pcolormesh(). For this purpose, I need to transform a meshgrid of x and y ...
1
vote
0answers
875 views

How do I change from lat/long to a metric coordinate system in GRASS?

Yes, it's yet another transformation question. I am working with ASTER DEM data, which is LatLong WGS84. I want to process the DEM map into an STL file for use in a CFD simulation. The script I am ...
1
vote
0answers
157 views

proj/pyproj converted coordinates offset

I'm using pyproj to convert some coordinates from WGS84 to OSGB36. When mapped out the converted and unconverted don't map to the same places on a map. The OSGB36 coordinates are mapped about 100 ...
1
vote
0answers
592 views

How to set Scale Factor for Lambert Conformal Conic (LCC) projection in ArcGIS Desktop?

The projection for my state according to my country's Mapping Agency is in a specific Lambert Conformal Conic (LCC) projection. They have given values for the following parameters: False Easting ...
1
vote
0answers
90 views

Spot NDVI spatial reference system

I have a series of spot NDVI data for Australia and I need to extract some information from it. Unfortunately there is no spatial reference system attached to it. This is one example of the data (HDF ...
1
vote
0answers
165 views

How to define coordinate system and geographic transformation for a CAD drawing?

I am a GIS guy and I occasionally work with CAD files as well. Now I need to know how I can define a coordinate system and a geographic transformation for a CAD Drawing. According to ESRI: "You can ...
1
vote
0answers
57 views

How to identify grid shift file used by osgeo in Python?

I wrote a Python script reprojecting points from a source coordinate reference system (SCRS) to a target one (TCRS) both identified by an EPSG code. I would like my python script to retrieve details ...
1
vote
0answers
234 views

Adding X,Y data and viewing with existing shape file

Excuse me for a simple question. I have CSV files of X,Y data (in decimal degrees) that I want to add to a map and view with a shapefile of level III ecoregions that I downloaded from the USGS ...
1
vote
0answers
110 views

Coordinate system for map downloaded Digimap?

I have download a 1: 25000 map from Digimap. It came as a tif file along with a tfw file. When I try to import the tif file as a raster layer, I get the following message: 'this layer appears to have ...
1
vote
0answers
411 views

Importing GPS coordinates correctly

I am importing a gsx set of waypoints with lat/lon taken in degrees, minutes, and thousandths of a minute. When they are added to my project, the waypoints are not showing up correctly - the ...
1
vote
0answers
333 views

ogr2ogr failed to reproject shapefile error exceeds limits

I cannot get correct transformation from WGS84 to the Hungarian EOV EPSG:23700 (Hungarian Datum 72) using ogr2ogr. I am using ogr2ogr from the fwtools shell. I have a shapefile in GCS WGS84 (epsg ...
1
vote
0answers
283 views

Create IPoint with Lat/Long in decimal degrees and Z in feet

I have written an ArcMap v10 AddIn that reads a folder of geotagged JPEG's and creates a new feature class where each point is the geotag information from on of the JPEG's. The issue is: The GPS ...
1
vote
0answers
273 views

Spatial Reference and Area/Length Attributes relationship

I currently allow users to add a shape file in. From the shape file, allow the user to generate a new layer base on the polygons from the shape file's polygon they imported. Generating the new ...
0
votes
0answers
26 views

Longitude and Latitude Mixed Up on Map

I am trying to map a WFS layer with data originally coming from a PostGIS table, and using a OpenLayers 3. At some point in this process, I believe the longitude and latitude coordinates are getting ...
0
votes
0answers
35 views

How to create a map in Pulkovo 1942 with grid?

I have a problem with coordinates when I change projection. With WGS 84 it's fine, I have normal, geographic coordinates. But when I'm changing to Pulkovo 1942 (I need a map of Poland), coordinates ...
0
votes
0answers
45 views

How do I display 2 layers with different coordinate systems in ArcGIS10.2?

I have a problem when I have to display 2 different layers (one dtm and a shape file). the dtm has GCS_CH1903_Bern coordinate system and the shape file has GCS_CH1903. I saw that the difference is not ...
0
votes
0answers
28 views

Storing 3D Oracle sdo_geometry objects with a 2D SRID

I'm trying to understand the implications of storing 3-dimensional sdo_geometry values in Oracle when the geometry's SRID is a 2-dimensional system. The database I'm studying uses SRID 4326 (WGS84 ...
0
votes
0answers
16 views

Is there a way to include code/language for offsets within the “script” at the CRS dialogue screen

I'm pretty new to QGIS and coming from being just good enough to be dangerous in Manifold GIS. I have some JPEG 2000 rasters that were exported from Manifold in UTM 18S, and then imported into QGIS, ...
0
votes
0answers
44 views

Improving accuracy of mercator meters conversion to lat/lon

My question is an extention to a previous post I had here a couple of weeks ago (converting-mercator-meters-without-utm-zone). While the answer in the previous topic got me so far, I've now come to ...
0
votes
0answers
36 views

Setting raster resolution in meters when working in a Geographic Coordinate System

I work in WGS 84 (Geographic Coordinate System) in ArcGIS 10.1. I need to create a raster specifying its cell size in meters, and output it in WGS84. Is it a good solution (towards a less shape/area ...
0
votes
0answers
24 views

How can one use Google Maps API to mimic QGIS projection/CRS

I used QGIS to find the extents of a list of features. However, the resulting data auto-generates the CRS and changes it from WSG84 to a custom one. Is there a way to use the autogenerated CRS in ...
0
votes
0answers
32 views

georeference a grid by using a script

I've got an image and a set of coordinates, which represent a grid, that looks similar to this: What I'm looking for is a script, that would transform my image, by using such a grid. Edit: My ...
0
votes
0answers
87 views

Creating a custom Lambert Conformal Conic projection in ArcGIS 10.1 and/or 10.2.2

referring to the table below, I am trying to use the values on the left from another program that uses different terms for the parameters of a custom projection. I just wanted to make sure that ...
0
votes
0answers
40 views

How can I define coordinate system of feature class when overlaying with coordinate zone shapes in python?

I have generated bounding boxes for CAD drawings that do not have defined coordinate system files. I know that each drawing could be in one of 6 different systems that do not overlap. My idea was to ...
0
votes
0answers
70 views

I am getting NULL values when I use “point sampling tool”?

I am trying to extract values from a raster using a point shapefile, but I am getting NULL values. I think that NULL values are obtained because the Coordinate Reference System (CRS) are not the same ...
0
votes
0answers
41 views

Comparing datums with GDAL/OGR

I have a bit of code in Java that takes in a SpatialReference object and checks that it is one of the acceptable datums (WGS84, NAD83, NAD83 HARN, NAD27), but because of the lack of standardization in ...
0
votes
0answers
27 views

gdal_grid data from 2 different utm zone

I'm developing a component which grid data over Vietnam region using gdal_grid from gdal. Follow gdal example I've successfully griding data within 1 specific UTM zone. However, for data over the ...
0
votes
0answers
95 views

Java GeoTools - Getting CRS from SRID

I might confuse between two things, but I need to do some calculation on my polygons (distance, area etc.). Using the WKBReader, I'm getting the geo: WKBReader wkbReader = new WKBReader(); byte[] a = ...
0
votes
0answers
40 views

Error 14: Could not open CRS database

I am using Python Console and loading a Vector Layer using python commands. When the layer is added, QGIS first asks for the CRS to use, but I don't have all the CRS listed out to select the Reference ...
0
votes
0answers
41 views

Convert coordinates

I have some data that I need to convert to Lat-Lon in order to plot. It originally came from an Esri Shapefile which I managed to get it out of with QIS. The issue is that the coordinate reference ...
0
votes
0answers
14 views

Layers change position when saving to another data format

When I save my map after using the composer, the layers move a little bit on the images of the OpenLayers plugin. It is like they ignore the CRS option. Do you have an idea?
0
votes
0answers
44 views

How to specify WGS84 CRS when importing a Shapefile into Idrisi?

Could you help me, please, to open shapefile from QGIS to Idrisi. I'm having problem answering to the Reference system, the project is using WGS84 but that is not in the Pick list. Idrisi is asking ...
0
votes
0answers
49 views

Issue on Setting Coordinates for SVG Map

Can you please help me to figure out how to set coordinates for BC Canada , based on following snippet. This code is setting coordinates for French as the 43.15710, 8.17199 is the lower right point ...
0
votes
0answers
67 views

I had an error in Gdalwarp and i don't know the reason

I was trying to warp a raster using a mask and shift it before clipping but when i exectute the command bellow in Qgis/PyQt using QProcess: gdalwarp -s_srs "+proj=merc +a=6378137 +b=6356752 ...
0
votes
0answers
71 views

QGIS convert attribute table to point shape

I have imported an attribute (whith no spatial information) table from MySQL. Fortuantly it has two colums with Longtitude and latitude taken from google maps. Is it posible to use those values to ...
0
votes
0answers
138 views

How to export raster from ArcGIS for Desktop to MATLAB using Tiff without losing projection?

How do I export data from ArcGIS for Desktop and import to MATLAB using Tiff without losing projection (lat lon) information? ASCII is too slow for my application. I manage to export a raster ...
0
votes
0answers
20 views

Can't save custom CRS in QGIS 2.0.1

I am trying to enter a custom CRS in QGIS 2.0.1 but when I enter the proj4 parameters and hit okay they are changed. There is no save open in 2.0.1 which seemed to be the problem for many people ...
0
votes
0answers
133 views

Understanding Scale and Resolution between WGS84 and Web Mercator

This might be very basic question, am trying to understand the relationship between scale, resolution and coordinate system. First, let me explain the problem I have a web mapping application (using ...
0
votes
0answers
35 views

QGIS layer only displays when I uncheck on-the-fly transformation

I have a layer that covers the stats of Indiana that has the following Layer SRS: +proj=utm +zone=16 +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs It will not display unless I uncheck the ...
0
votes
0answers
58 views

recalculate latitude and longitude from a pixel in a cropped map

i want to recalculate a geographic coordinate from a pixel in a map. For this i have the size and the coordinates from the map to convert a coordinate to a pixel is use the algorithm, you find at ...
0
votes
0answers
15 views

How Do I simply display the Coordinate Info of any vector format (.Shp,.gdb,.mdb) in a textbox using VB in ARCGIS

I've made an interface using VBA Macros to show the existing coordinate system information of the input vector file in a textbox by clicking on code button. And if I defined the projection and if it ...
0
votes
0answers
58 views

Coordinate points don't show on correct location in the open layers plugin Qgis

I know there are several questions concerning the open layers plugin and CRS's. I tried several things, but none of it solved my problem so far. For a rural area in Nepal a little healthcentre wants ...