nav[aria-label="Primary Navigation"] { padding: 0; & ul { list-style: none; width: 100%; display: flex; flex-direction: row; justify-content: start; align-items: start; gap: 30px; padding: 0; & li { margin: 0; } & ul li { list-style: none; } } }

Calculating number of cells/area of one layer in a map (trying to use Tabulate Area)

AndreaGG6

Hello again! I'm still a newbie in arcgis and I'm having troubles with one of my assignments:

I created a corridor model because I wanted to create the most suitable path where mountain lions can cross. In my screenshots, I'm showing this path created by running the corridor model (purple line between sites) however, I would like to integrate this data with another one of my layers. For instance, I would like to know how much of these paths are protected in the various protection statuses. I have protection statuses ranging from values 1 to 4 (least protected to fully protected) as you can see, so I would like to see how much of these land covers are the corridors involved in? I tried to do this by using Tabulate Area tool, but when I try to specify my paths as an input raster, the software is detecting them as an invalid extent Any ideas of how I can do this?

Encontre mais publicações marcadas com

Analysis

Content Management

Geodatabase

Desktop

Feature Services

Accepted answers

DanPatterson

Something is still bothering me still.

Use Copy Raster and save both files to a new folder (short, no spaces, no fluff, like "C:\work")

Make sure that you specify a *.tif output, not an esri raster or any other format,

Make sure that you specify the cell size, snap raster and extent to be that of you cats layer.

Then do the work. If all else fails, you can zip and attach that folder with the two tif files. so we can have a look if needed

All comments

DanPatterson

Are both files in the same coordinate system? And is that coordinate system a projected one?

What exactly was the extent set to? (you do that through the Environments tab of the tool)

AndreaGG6

Both layers are projected in NAD 1983 Zone 11N (meters) and my map coordinate system is WGS 184 (decimal degrees). I set the output coordinate system in Environments as NAD 1983 too. Could the map units be the problem?

DanPatterson

NAD 1983 is a datum, not a coordinate system.

IF both layers are in your UTM NAD 1983 Zone 11N, then set your map units to it.
This means you must have something in your map that set the units to decimal degrees (with a NAD 83 datum).

Open a new map, move your two layers into it, check to see if the map is set to the appropriate UTM zone.

If your area of interest is limited, I would clip to a smaller extent that to minimize calculations.

Then do your tabulate stuff.

But again, confirm the coordinate system (even checking the raster extent to make sure they are in meters)

Good luck

AndreaGG6

Okay

-Everything is set in meters

-Map display units are set to meters
-Extent of ALL layers is set to meters
Output coordinate system on environments are set to NAD 1983 UTM Zone 11N just like the layers but still can't run the tool. **Could I be using the wrong tool for my purpose?

DanPatterson

Still not convinced about your coordinates.

This is what coordinates should look like for a mercator style projection (MTM is similar to UTM).

Notice the big numbers, I am at latitude 45ish N, so I am about 5 million meters from the equator. If your properties show really small values, then your raster is in decimal degrees and your raster isn't projected.

Do this for both.

Tabulate by area will work IF everything is correct.

You could use other methods, like "Combine" which would produce a new classification showing where

class A in raster 1 matches with the various classes in raster 2 ... etc for the various combinations in both rasters. Then you have to figure out how much.

It is the little things,

like mismatched extents,
wrong projectiong,
different cell sizes (haven't gotten around to mentioning that yet)
snap raster not specified
raster projection method
plus more

Now since this is an assignment, and I taught for many years... remember, it isn't the answer but the journey to it, so document everything that you have done and tried... even if it doesn't work out!!!

Tell your instructor I said so 😉

JayantaPoddar

Could you share the screenshots of extent and spatial reference of Mountain_Lion_Corridors layer?

AndreaGG6

Sharing the map properties, extent and spatial reference of both layers I'm trying to tabulate

map extent.png map properties.png

JayantaPoddar

The extents look just fine as per the Spatial Reference. Fill all the required parameters (including output table), and try to run the Tabulate Area tool. Let us know if the issue still persists, or a new error message pops up.

DanPatterson

also try saving to a new location. Extents do look fine. Protected status is bigger (quick mental math),

you may want to set the analysis extent to that of the cats since that is the area you are interested

Now. If that doesn't work, clip both, save both to a new files (Copy Raster tool)

DanPatterson

Something is still bothering me still.

Use Copy Raster and save both files to a new folder (short, no spaces, no fluff, like "C:\work")

Make sure that you specify a *.tif output, not an esri raster or any other format,

Make sure that you specify the cell size, snap raster and extent to be that of you cats layer.

Then do the work. If all else fails, you can zip and attach that folder with the two tif files. so we can have a look if needed

AndreaGG6

Copy raster works! layers output as tif allowed me to tabulate.. I can't thank you enough and I'm learning a lot thanks to you all. Just for my understanding, why did this solve the issue?

DanPatterson

*.tif format are the preferred raster format for most spatial analyst functions.

The old-school raster had big issues with file naming conventions and the geodatabase rasters... well never used them, I just know from that many a question has been saved by saving as tif in a local folder.

Having said that, I usually use numpy for a lot of my raster work since it truly designed to work with array data (aka, rasters) ... but save that for when you have a few more days of learning 😉

Remember to document your new find in your assignment.

Participe da Conversa

Membros conectados podem postar, seguir atualizações e mais. Novo aqui? Registre uma conta gratuita.

Links Rápidos

Community Help
Find useful guides, FAQs, and documents to help you navigate and make the most of Esri Community.