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14

Ok, so this answer works for the Anaconda 64bit Python distribution with ArcGIS 10.1 64bit on Windows 7/Windows Server. Some of (or all) of the tips given below may apply to any other windows distribution of python. First, install anaconda, it should go to the directory C:\Anaconda. Check the box 'make system default python'. It may give a warning that ...


13

See the OGR Projections tutorial and the OGRSpatialReference class. In particular, the GetAttrValue method. Here's a worked example. from osgeo import gdal,osr ds=gdal.Open(r'SOMERASTER.TIF') prj=ds.GetProjection() print prj srs=osr.SpatialReference(wkt=prj) if srs.IsProjected: print srs.GetAttrValue('projcs') print srs.GetAttrValue('geogcs') For my ...


12

Something like this should work: def reverse(s): items = s.split() digs = ''.join(i for i in s if i.isdigit()) dr = digs[::-1] return ' '.join(map(None, items)).replace(digs, dr) >>> reverse('321 test') '123 test' @mnpeterson brought up a good point about assuming where the numbers are...My post above would string all digits ...


9

If an unhandled exception, such as an ImportError, occurs before the add-in classes are instantiated they will become unresponsive, be given a [Missing] label, and have a red symbol for their icon in the case of items on toolbars or in menus: You can confirm whether an import error is happening by wrapping your import statement with an exception handler ...


8

You're doing your installation wrong. Instead of pip install shapely use the Windows installer available at https://pypi.python.org/pypi/Shapely#downloads And click on the file Shapely-1.2.17.win-amd64-py2.7.exe Launch the install and it will be OK after. Just as an information, "pip install shapely" works when you have the C compiler installed to ...


8

In cursors, length is a read-only property. I couldn't imagine what a predictable outcome would be for setting a new length of a line. Would it just extend the last point out in the bearing from the next to last point? What if it were multipart? Would it grow the entire polyline segment by segment?


7

use QgsMapLayer::loadNamedStyle uri = "/home/user/style.qml" layer.loadNamedStyle(uri)


7

Is this homework? for fc in arcpy.GetParameterAsText(0).split(";"): arcpy.AddMessage(fc) arcpy.AddMessage("No more shapefiles")


7

This sort of question is better answered in StackOverflow but the answer is straight-forward enough so I'll give you a hint here. Your date is not a date as far as Python is concerned but a division sum - which is the main reason why it doesn't work. Your code also won't give you the last four digits. You need '[-4:]' (yours gives everything except the ...


7

I can crush this down to 3 lines of code, no cursors required! import arcpy arcpy.SpatialJoin_analysis("Site", "points","in_memory/points_SpatialJoin", "JOIN_ONE_TO_MANY", "KEEP_ALL", "", "INTERSECT") arcpy.Statistics_analysis("points_SpatialJoin", "in_memory/stats", "Join_Count SUM","Id") Then simply sort the table to find the polygon with most points.


6

>>>'R12345678910'[1:] '12345678910' Edit Appending [1:] to a string in python will remove the initial character. Look up slice in the python help. To use this in the ArcGIS field calculator, you will need to turn on Python parsing for the unitCode = enter !your_field_name![1:]


6

You can actually deal with each part of a multipart polygon by creating a separate polygon object. Take a look at the following code. import arcpy from arcpy import env env.workspace = "C:/Data/Exercise08" fc = "Hawaii.shp" for row in arcpy.da.SearchCursor(fc, ["OID@", "SHAPE@"]): print("Feature {0}: ".format(row[0])) partnum = 0 for part in ...


6

It looks like you are missing another zone = cursor.next() within the While loop You need to increment the cursor to the next feature after you're done with it or the loop starts over on the same feature. incidents = r"c:\users\documents\arcgis\arcgis tutorials\psu tutorials\project3\policedata.gdb\GraffitiIncidents" patrol_zones = ...


6

As already been mentioned in GS exchange, the QGIS version of Kyng Chaos uses the standard Apple Python and the version 2.x (and not the 3.x, nor others Python implementation, Homebrew, Anaconda, etc.) As indicated in the documentation, you must first add PyQGIS to the PYTHONPATH I use here the Terminal application: export ...


6

Ok, I'm sorry to post a question and then answer it myself so quickly, but I found a nice set of course slides from Utah State University that has a lecture on opening raster image data with GDAL. For the record, here is the code I used to open the PRISM Climate Group datasets (which are in the EHdr format). def ReadBilFile(bil): import gdal ...


6

First case: insert new polyline You have to define the Polyline like so: pLine = [QgsPoint(1,1), QgsPoint(2,1), QgsPoint(2,2)] it is a list-of-QgsPoint. After you can put more QgsPoint into the list by append to insert the element at the end of the list: pLine.append(QgsPoint(3,2)) or inserting some vertex point at a specific location of the list: ...


6

in provides a quick logical test for determining if a value is contained in a list, dict, or string. if from_g in dct_max: either from_g is found in dct_max (true) or it's not (false). The rest of your questions would be resolved by researching how dict objects work (lots of good examples on Stack Overflow).


5

Based on your results, it looks like field1 may have a space (" ") in the field, instead of an empty string. def concat_fields(field1, field2): if field1.strip() == "" or field2.strip() == "": return "" else: return field1 + field2


5

Did you check this page? It may give you some idea how to set it up: http://grasswiki.osgeo.org/wiki/GRASS_and_Python -> Creating Python scripts that call GRASS functionality from outside --> MS-Windows


5

If you add a geoprocessing tool to a toolbar it will run immediately upon clicking it, provided it has no parameters:


5

getClass (In , Out , Therid, freq ) if FREQUENCY== 1: return str(In) elif FREQUENCY== 2: return (str(In) + "-" + str(Out) ) elif FREQUENCY == 3: return (str(In) +"-" + str(Out) + "-" + str(Therid) ) else: return "other frequency" here is a quick fix. Concantenation in Python uses "+", and I converted ...


5

You need to break it down to points if they're good points and reconstruct. Polylines are made from paths, polygons are made from rings. Although they are created in a similar way they are not compatable, hence your error. Go through each point on the line adding a point to your output array and then insert. here's a post that might help Get all the points ...


5

The following approach uses a Search Cursor and Python dictionary to perform the following workflow: Select points within each polygon feature Update dictionary with key (OID) and value (point count) for each iteration Find max point value and corresponding OID and write to a text file import arcpy, os points = r'C:\temp\mytest\points.shp' polys = ...


4

VBScript Example: Right( [FieldName], 11 ) This code will take the 11 characters from the right, and anything left of those 11 characters is omitted. Python Example: !FieldName!.lstrip('R') This code takes a string and removes R from the left/front of it. Both of these examples should get rid of the R in your strings. Edit: Regan Sarwas' updated ...


4

In the line where you call arcpy.Clip_management you reference r'optfile/ras1' which is a string, you want it to be: os.path.join(optfile,ras1) so that you can make use of the variable.


4

Under the hood QGIS uses GDAL/OGR for most of the functions. So, the Python API for GDAL would be the closest analogy to using ArcPY in a stand-alone situation. You can use the installation that comes with QGIS or have a separate installation of Python and GDAL. Other addons that complete the 'package' I would include Shapely Numpy SciPy The last ...


4

The syntax is Dissolve_management (in_features, out_feature_class, {dissolve_field}, {statistics_fields}, {multi_part}, {unsplit_lines}) You need to specify the dissolve_field as the third parameter - here you've left it blank.


4

The API docs state Memory data providerType (memory) The memory data provider is used to construct in memory data, for example scratch data or data generated from spatial operations such as contouring. There is no inherent persistent storage of the data. The data source uri is constructed. The url specifies the geometry type ("point", ...


4

First make sure you have the 32 bit PyScripter installed, not the 64 bit. Then in Tools -> Python Path make sure you have PyScripter pointing to the following paths: C:\Program Files (x86)\PyScripter\Lib\rpyc.zip C:\Windows\system32\python27.zip C:\Python27\ArcGIS10.2\DLLs C:\Python27\ArcGIS10.2\lib C:\Python27\ArcGIS10.2\lib\plat-win ...


4

You're nearly there, you just need to accumulate. Start by initializing a variable (total) to 0 and then for each row add the value to the total like this: Total = 0 field = "Tot_Aff" cursor = arcpy.SearchCursor(fc) for row in cursor: Total += row.getValue(field) print("Total is : %d" % Total) Null values will mess with this, to keep it simple I ...



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