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1

I suggest that you replace the .prj of your shapefile (same name as the other files ) with the prj from Spatial Reference site, which seems to be correct. The difference in X and Y northing comes from the conversion in feet. Probably this is a rounding problem for the two WKT. PROJCS["NAD83 / California zone 3 ...


4

Maksim already provided the answer with ArcGIS, so here is the (very similar) QGIS solution right click on your shapefile to open its attribute table click "toggle edit mode" button (a pencil) (or ctrl+E) on the right, click the icon for field calculator (an abacus) (or ctrl + I) write sqrt(name_of_field) Note that you can check "create in a new field" ...


4

Using Field Calculator, either VB Script Sqr([FIELDNAME]) or Python math.sqrt(!FIELDNAME!) under the Number Type will yield square roots. You can either calculate into a new field, or on the field itself.


1

The elevation service on ArcGIS Online includes ready to use worldwide data, and also a built in raster function to generate aspect. It's also pretty simple to filter simultaneously for a range of aspect values (290-250 degrees) as well as elevation (e.g. 0 to 10 meters, depending on how you define a beach - or perhaps you already have the beaches ...


1

You need to digitize the boundaries (assuming a search online has drawn a blank for any existing datasets - that would be my first port of call!). To digitize the boundaries, there are several approaches you can use but I would start by creating a line-dataset that represents the boundaries. At the coastline, extend the boundaries into the sea so they ...


1

Unless the borders are coloured in a unique colour, you have to digitize the borders as polygons manually. There is no tool that can digitize monochrome line patterns if they lay over other map objects of the same colour like roads and rivers. Make sure that your boundary polygons snap to each other. I use a snap radius of 10 pixels (not Map units!) for ...


7

In the field calculator select "update the column" where you have numbers and use this string "COLUMN_NAME" || ' M' If you just want to label them with the 'M' paste the same code in the "expression based label panel".


3

Shapefiles have no type MultiPolygon (type = Polygon), but they support them anyway (all rings are stored in one polygon = list of polygons, look at GDAL: ESRI Shapefile) It is easier with Fiona and Shapely: import fiona from shapely.geometry import shape, mapping # open the original MultiPolygon file with fiona.open('multipolygons.shp') as input: # ...


4

from GDAL mailing list using python import os from osgeo import ogr def multipoly2poly(in_lyr, out_lyr): for in_feat in in_lyr: geom = in_feat.GetGeometryRef() if geom.GetGeometryName() == 'MULTIPOLYGON': for geom_part in geom: addPolygon(geom_part.ExportToWkb(), out_lyr) else: ...


-1

Try opening your .prj files in a text editor (Notepad, Notepad++, etc.) and then check out the text there. If the CRS saved correctly it should say: PROJCS["NAD_1983_StatePlane_Texas_Central_FIPS_4203_Feet", GEOGCS["GCS_North_American_1983", DATUM["North_American_Datum_1983", SPHEROID["GRS_1980",6378137,298.257222101]], ...


2

Instead of Intersect, use Clip. Vector > Geoprocessing Tools > Clip


0

Exkoria, I know you're using QGIS, but I figured I'd post this code from ArcMAP in-case you can get some help from it. It pans to each feature in a shapefile and exports an image, and then repeats for all features in the shapefile you specify. Like I said, its not QGIS, but it might help somehow. # This script pans ArcMap, once for each feature in Layer ...


0

I don't know how it is working but these piece of code works. vlayer = QgsVectorLayer("home/sanjayr/Desktop/india-latest.shp/buildings.shp","sanjay","ogr") QgsMapLayerRegistry.instance().addMapLayer(vlayer)


0

geocat offers a commercial ArcMap plugin called 'Bridge' that can convert all of your ArcMap symbology to SLD (there is an open source alternative arcmap2sld). In QGIS you can import SLD and use this as style for QGIS layer. In bridge the tree structure of the TOC is exported as WMC, and the data as shapefiles (including metadata .shp.xml) and tiff's. I ...


2

Judging from the coordinates we can see on your second screenshot (-99,30), I think that you changed the layer CRS in layer properties instead of properly reprojecting the data to state plane. Reproject the layers and try adding the scale bar then.


3

if not availble you can always create your own convertion function: http://nathanw.net/2012/11/10/user-defined-expression-functions-for-qgis/ and should be good to share it in some place or to propose to insert in the expression library


2

Kadeem's modified answer will prevent your features from being visible, but they will still be present, if you are trying to identify an individual ship track you may click an invisible feature by mistake. What it seems like you need to do is define your layer so that it's as if those features don't exist. In ArcGIS this would usually be done using a ...


0

Perhaps use the Spatial Query to select all lines that intersect or touch or overlap other lines. Then could you invert the selection (to select all lines that do not intersect, touch or overlap) and delete the lines? Perhaps the topology checker could work to help you select or identify lines not touching other lines.


3

Open the "Layer properties" and go to the "Fields" tab. You will see a column "Alias". Whatever you enter there will be used throughout the user interface.


2

Yes you can do it with fewer values, depending on the combinations you want of course. In the Data Defined Properties section, click on the curly E button to define an expression. When the Expression dialog box opens, you will probably want to define a conditional expression. Use the CASE ELSE option and create an expression something like this (for the ...


1

I'm not sure if I understand you correctly but if You're trying to translate english names of columns into your local language automaticaly I think you can't do this in QGIS. The only resolution that I mind is creating a view on database and show this view in QGIS Create view translated_table as select id as translated_id, field2 as ...


2

I haven't tested this but perhaps this might help: Settings > Options > Locale EDIT: The only other method I can think of is: Add Vector Layer > Encoding And select whichever one you think is suitable. Hope this helps!


0

The open-source GIS Whitebox Geospatial Analysis Tools has a tool called Extend vector lines that can be used to perform this task exactly. From the help documentation: This tool can be used to extend vector lines by a specified distance. The user must input the names of the input and output shapefiles, the distance to extend features by, and whether ...


0

Based on your comments, the problem is solved. In summary: 1-Using the excel tool, here, Excel tool for converting LatLong to UTM. In the Batch Convert LatLong to UTM sheet, paste the LatLong coordinates into collumn L, M then, the UTM coordinates are automatically calculated and save in AE,AF collumn. Saving the UTM coordinates to a file. (This step also ...


1

This One has step by step tutorial. Hope you like it. QGIS http://www.qgistutorials.com/en Quickstart Making a Map Working with Attributes Importing Spreadsheets or CSV files Using Plugins Searching and Downloading OpenStreetMap Data Basics GIS operations Basic Vector Styling Calculating Line Lengths and Statistics Basic Raster Styling and Analysis ...


0

A very godd source is locate Press. The company specialized in books about the Qgis and GIS. It has some titles that have come out and some that are under publication and of course all is printed and e-book. The book of locate Press is: The Geospatial Desktop Open Source GIS and Mapping The QGIS Training Manual A Comprehensive Introduction to Quantum GIS ...


0

You can use QGIS for georeferencing (tutorial), then generate tiles with it (another tutorial). Finally, you should specify layer bounds in Leaflet tile layer with bounds option.


2

you can store your annotation in point layer. and label it to [Right click >> Properties] use as annotation layer. Follow simple steps below: Make sure your point feature is not visible. only the label is visible. Right click on layer >>properties>> Style tab. Select Simple marker or simple choose any hollow marker and set Size to 0.00000 as shown in ...


1

Easiest solution would be to create a buffer of 20m around your polygon, and clip the grid to that. You can always re-clip the grid to the exact polygon later.


3

You don't have to save your annotations as a layer. Simply toggle the Text Annotation function in the toolbar and press Ctrl + T to switch it on/off. Your annotations will be saved within your project.


4

Here's how to access that setting. First open the layer properties by double clicking a layer, then go to the labeling tab. Look for the button in the top-right of the window (shown below): Then, switch off "show partial labels": This setting applies to all labelled layers in your project.


1

For QGIS on Mac, the Kyngchaos.com installer package is built against the GDAL_Complete installer framework from the same site, as is noted under Requirements on the download page. It will not work with gdal from the Homebrew project. If you want to go with a purely Homebrew approach, try the OSGeo4Mac project. First run brew unlink qgis, which is the ...


3

Kristina, I assume there is an attribute in your table which allows you to identify a single track? For example: point_id | track_id ------------+------------ 1 | 15 2 | 15 5 | 24 6 | 24 7 | 24 If you open the attribute table, you can find an epsilon symbol (in the figure below, the ...


2

There is two ways: you can transform the raster to vector and then merge the two vectors. you can extract the centroid of the counties and then extract the values of the raster in this points.


3

As Pat has mentioned, you cannot merge different geometry types together, just as you cannot merge polygons and lines together, or points with polygons. Your question needs to be edited to provide more information as to what you are hoping to do, or have as an outcome. If you have if you want to merge two datasets together to get more area, then convert the ...


9

My approach would be to: Create a buffer around your points using radius field; Union all resulting features; Create a new buffer of exagerated size around it (according to your data two different point seams to differs in around 20000 m, so I would use this value); Then create an inverse buffer of it (-20000m); might need to simplify the result. I think ...


1

QGIS Server has some limitations but you can add Lizmap on top and get more functionalities. The documentation is pretty good but it lacks a good English translation from french. It handles users/groups. Cache management Bing, Google, IGN, OSM base layers You can easily build html popup for getFeatureInfo calls. The Lizmap plugin is very handy and gives ...


2

Extract centroids of the lines, use the field calculator to create two attributes in the table: one with the x coord and one with the y. If the grid is regular and lines are not broken at each intersection, the horizontal lines must have all the same y coord. Select this points, and use this selection for a spatial query that selects the lines that ...


2

Why not just select all horizontal lines, start editing and use the delete features button? You can use the "Select by rectangle" tool, and draw a tall, very thin rectangle between two vertical grid lines to get all horizontals selected


1

Supposed you have created the grid as lines and not polygons: switch the grid layer to edit mode select the rightmost vertical line by rectangle with strg key pressed, unselect that line by clicking on it Press Delete Selected icon.


3

I found this gudie by Anita Graser a couple of days ago, and it looks like just what you need: http://anitagraser.com/2014/05/31/a-guide-to-googlemaps-like-maps-with-osm-in-qgis/ Using that method you can define the lat-long box that you are interested in and apply it to .pbf file downloaded from the Geofabrik site.


-1

I highly recommend to use the stable version of Grass (i.e 6.4.4.1). Regards,


1

The first source you mention remarks: All these formulæ are for calculations on the basis of a spherical earth (ignoring ellipsoidal effects) so you should not rely on the results. If you use the openlayers plugin, project CRS should be set to EPSG:3857. As Erica points out, that is not suitable for measurements. For measuring, delete the ...


0

I think this is a projection-related issue. WGS84 is not intended for accurate measurement anywhere but the equator, so the measure line tool (or a scale bar, if you were making a map) would be off. The Haversine calculation is independent of projection and so its results are reliable. Refer to this question: Problems with scale bar units in qgis composer ...


0

To add info to an existing layer instead of in memory layer you need to point to a layer on disk with QgsVectorLayer: vl = QgsVectorLayer("C:\Temp\pt.shp", "pt", "ogr") Then you may continue to reference the code snippet from this Q/A: How to create a new empty vector layer programmatically?


1

This particular way is currently not possible with QGIS (at least not without an advanced plugin) However, an alternative approach be almost what you want without any python at all and without adding custom buttons. Select some features Open the attribute table and switch to form view (See highlighted button in picture). Choose "Show Selected Features" ...


0

QGIS now has a very impressive rendering engine which you can use to drape one image over another. For example you can get a nice "3D effect" by draping an ortho-photo over a hillshade raster. You set the rendering in the first raster's Layer Properties page on the "Style" tab. There are several kinds of rendering, the "Darken" or "Multiply" options gives an ...


2

You can create another layer, draw a box by your coordinates and follow the already referenced answer How to crop Shapefiles in QGIS?. I would myself use ogr2ogr with the -spat parameter. If you want also to clip the selected features with the selection box use -clipsrc [xmin ymin xmax ymax]| http://gdal.org/ogr2ogr.html QGIS Processing toolbox has a ...


1

You could use regular expressions to do this: regexp_match( "NRN",'(\\b|_)(1|2|23|31)(\\b|_)') This will match either a "1", "2", "23" or "31" which is surrounded by "word boundaries" ( \b") or underscores. (A word boundary is either the start or end of the string, or certain whitespace characters). New numbers to match can be inserted into the ...


0

If you change the NRN field from 20_21 to _20_21_ then you can use "NRN" LIKE '%_21_%' to find all features which contain the number 21.



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