POST

I have been sent some data that I need to project in Arc 10.4.1. The data is in two formats: .GRID and .AGR. The .GRID files are a DEM and the .AGR are ice thickness measurements. When I 'add data' in Arc or access the folders through the Arc catalogue, I can't see either of these file formats. Can anyone advise me on how to display these files in Arc? What software can I use to convert them into a usable format? Thanks
... View more
12292016
02:45 AM

0

0

933

POST

near_delta is set to True I've done a computation of the z value in the table and it worked fine. Both are in the same coordinate system
... View more
10272016
04:58 AM

0

1

102

POST

I am using the Near 3D tool in Arc 10.4.1 (basic licence) to compare two point shapefiles, both of which have z values. I am interested in the nearest delta x, y and z values between the two sets of points. When I run the tool, I get correct outputs for delta x and delta y but the delta z column returns only values of 0. The z coordinates for the nearest point is also shown as 0, despite the every point in the shapefile having a z value. Can anyone suggest why I am not getting the correct delta z values and advise me on how to fix this issue, please?
... View more
10272016
02:50 AM

0

3

567

POST

I have Et Geowizards 11.3 installed for Arc 10.1 and have added the ET Geowizards toolbox to the ArcToolbox. However, when I try to run an ET Geowizard tool I get the error message 'Tool not licensed'. This also happens when I try to run ET Geowizard tool via the Model Builder. The tools run fine from the ET Geowizards dialog box. Can anyone explain why they tools won't work in the ArcToolbox or Model Builder? NB  what I really want to be able to do is to batch process using ET Geowizard tools. If I can get the tools to work in the ArcToolbox or Model Builder then I will be able to do this, but I can only run the tools for a single layer at a time in the ET Geowizards dialog box. Thanks, Camilla
... View more
06022016
07:47 AM

0

2

6188

DOC

Thanks for suggesting this. I'd not thought to put the code block in syntax format but it definitely improves the document.
... View more
04092016
07:55 AM

0

0

574

POST

I've written up the solution to this problem, including Field Calculator Python codes for straight line length, percentage slope and degrees slope. See this document for my writeup: Python code for straight line slope of a polyline (inc. straight line length, pecentage slope, and degrees slope)
... View more
03172016
05:32 AM

1

0

265

DOC

Follow these instructions to calculate the percentage and degrees slope for any polyline layer with z values. 1. Add fields to the attribute table for: a) straight line length; b) percentage slope; c) degrees slope. 2. Use the Field Calculator to compute the straight line length using this Python code. NB  if your polylines are straight, then you can omit this step and instead calculate the Length field using 'Calculate Geometry' as normal. Code block: import math def GetDistance(shape): distance = math.sqrt((math.pow(shape.firstpoint.x  shape.lastpoint.x, 2)) + (math.pow(shape.firstpoint.y  shape.lastpoint.y, 2))) return distance 3. Use the Field Calculator to compute the percentage slope using this Python code. NB  if you have straight polylines then you can subsitute the normal 'Length' field for the straight line length (called Straight_L in this example). Code block: import math def GetSlopePerc(shape, leng): ratio = (math.fabs(shape.lastpoint.z  shape.firstpoint.z))/ leng percentage = ratio * 100 return percentage 4. Use the Field Calculator to compute the percentage slope using this Python code. Note that Slope_pcen is the percentage slope field. Code block: import math def GetSlopeDeg(shape, percentage): ratio = percentage / 100 radians = math.atan(ratio) degrees = radians * (180/math.pi) return degrees Alternatively, you can return the slope in degrees using this maths module function: math.degrees() (Thanks to Neil Ayres for suggesting this alteration) Hopefully this has been helpful! Let me know if these codes through any errors for you.
... View more
03172016
05:30 AM

0

2

4736

POST

I've got it working. Unfortunately my university is tight and will only supply me with Arc 10.1, which doesn't have the Add Geometry Attributes tool. So I used the old fashioned 'Calculate geometry' function to add start and end z values to the attribute table. However, this was returning a z value of 0 for both the start and end points of every polyline. After a bit of snooping I discovered that the z values for the layer had somehow reset to 0. Presumably during some other processing I'd done previously. So I reextracted correct z values from a DEM of my study area. This got 'calculate geometry' to return the right z values and meant that my slope codes worked perfectly. Here is the final code for percentage slope (using straight line length between the start and end points): And here is the code I used to get slope in degrees from the percentage: Thanks for all your help!
... View more
03172016
05:16 AM

0

0

221

POST

I've resolved the NameError and the code is now executing. I have also computed the straight line length of the polylines sucessfully and substituted this field into the code in plac of SLength. This is my current code: At the moment this is only returning a value of 0. Working through the calculation for a couple of the polylines suggests that I should be getting values other than 0. Do you have any idea why I am only getting 0 values out of this code?
... View more
03152016
04:43 AM

0

2

221

POST

Hi again. I've only just had the chance to test these changes but the code is still returning an error. Here is my current code: This is the error that it is returning: Thanks for your other point about the straight line slope. On thinking about it I do think that I will need to use the straight line slope. So I will add another field to compute the straight line distance between the first and last points and will substitute this field for SLength.
... View more
03152016
03:55 AM

0

3

221

Online Status 
Offline

Date Last Visited 
11112020
02:23 AM
