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- About Kofi_Lartey
Kofi_Lartey
Deactivated User
since
06-20-2015
11-11-2020
74
Posts created
3
Kudos given
2
Solutions
4
Kudos received
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My Ideas
(0 Idea Submissions)Latest Contributions by Kofi_Lartey
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Hallo All, I am trying to use the raster calculator to calculate Slope length SL for my RUSLE model. All the necessary layers as inputs have been prepare including flow accumulation, slope in percentage. But when iinput the formula (see attached) and run the map algebra tool i receive an error message. Any ideas where i may be missing it?
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04-11-2016
05:00 PM
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@Dan you are right, but sometimes one is not sure what he may be missing.
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04-11-2016
10:52 AM
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I have prepared a land cover map, converted to a polygon and merged individual polygons in the various classes forming 10 classes. Now i want to find the percentage of each of the polygons. I used the statistics tool in Analysis, Arctool box to sum up the polygons but cannot join it to the main table because the objectID does not have any corresponding value in the main table. I am sure this is a simple thing, but somehow i am stack. I will welcome your suggestions.
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04-11-2016
06:51 AM
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@Dan I am looking at various options and then i will decide which could be useful, but that comment was very useful
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04-11-2016
06:42 AM
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Dan Patterson, I hope you will have time to comment on my latest post on some form of correlation analysis between rainfall erosivity and elevation
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04-09-2016
04:22 PM
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I am trying to do some form of correlation analysis between elevation and rainfall erosivity, but not sure whether this is the right way. I used the fishnet tool to evenly distribute a set of points over a polygon. Next i used the extract multiple values to point tool in spatial analyst - extraction to combine a DEM and the shapefile of points to extract from the DEM points with elevation and coordinates. Now the output will be joined to the rainfall erosivity map from which some form of correlation analysis can be performed, i believe. However there is a problem. The output from the multiple point extraction was two empty columns, one from the DEM and the other from the shape file. I believe i am not doing something right. I welcome suggestions to give me direction. Attached is the shape file
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04-07-2016
03:44 PM
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@ Dan, i agree with you and this is noted as one of the limitations of the map. I changed the extent in the environment setting and it worked. What i have is a rainfall erosivity map which will be used together with other maps to show a trend. The import of this is what can be done if data is available. Very grateful to all your useful and insightful comments.
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04-06-2016
11:54 AM
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The first map shows location of raingages and the second results of spline, but which covers only limited part of site. How do i extent it to cover rest of site
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04-05-2016
01:44 PM
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Dan Patterson, this is the latest on the rainfall erosivity map. I now have data from 6 different stations within the study site, which i used to derive rainfall erosivity values for between 40-11years period. I used the addxy coordinates tool to locate the raingages in a map and using the feature to feature tool in arcmap converted the processed data in excel into a feature. I tried using the Spline approach to interpolate the erosivity values to cover the entire site, i also used krigging but what i am getting is not what i want. How do i improve it. I am attaching two maps for clarification
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04-05-2016
01:42 PM
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I must admit i have been working but what i did does not really make sense and off course it didnt work. I first opened a new field in the map to be clipped and using the calculate geometry tool populated it. I also opened a new field in the clip polygon and populated it with Z values (1) before using it to clip but same response. I also degitized the clip polygon and tried to use the Sketch properties feature to give Z values to each of the vortexes (over 700 of them). But when i opened the attribute table there was nothing in it. Well i read that digitization was one means to add z values to a polygon, maybe i missed something. But i used it to clip and same results. What next?
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03-29-2016
04:09 AM
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Dan, No Z is not enabled but the attribute table has elevation values which when i added Z value and used Z coordinates to populate produced the same values as the elevation. The Z field in the table is populated with null values.
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03-29-2016
03:33 AM
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So all have been successful clipped, of course except those with z values. But how did you determine z value from the extent?
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03-28-2016
04:03 PM
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Chris suggested maybe its because of the z value in the data, so i tried other layers with no z values like roads and it clipped . I will try the others too and see what happens. If this is true then what will be my options?
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03-28-2016
03:33 PM
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Chris, you may have a point because i tried clipping other layers without a z value and it has successfully clipped. I am yet to try all the others. In the mean time, what are my options?
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03-28-2016
03:30 PM
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I use personal gdb because i assume it has a larger storage capacity since most of the data i am working with are very large, but i will try the file gdb too. All files within the ArcGIS environment are named without spaces between them. The clip layer is a polygon of my project site which is composed of several water sheds. Maybe i have to merge the delineated watersheds into one continuous polygon. I must add that the data to be clipped does not cover the entire area of the clop polygon, yet still the clip polygon will clip off the part that is of interest to me. Can you explain the implication of the extent overlap to clipping?
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03-28-2016
10:42 AM
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My kudoed posts
| Title | Kudos | Posted |
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| 1 | 01-25-2017 01:19 PM | |
| 1 | 03-21-2016 11:13 AM | |
| 1 | 02-24-2016 03:01 PM |
Activity Feed
- Got a Kudo for How do i clip a raster data to produce a smooth edge. 11-25-2024 11:12 AM
- Posted How do i get two raster cells to align? on ArcGIS Desktop Deutschland Questions. 03-01-2017 05:53 PM
- Tagged How do i get two raster cells to align? on ArcGIS Desktop Deutschland Questions. 03-01-2017 05:53 PM
- Posted Re: Is it possible to join a polygon to several sub sets within it? on ArcGIS Desktop Deutschland Questions. 03-01-2017 05:39 PM
- Posted Is it possible to join a polygon to several sub sets within it? on ArcGIS Desktop Deutschland Questions. 02-21-2017 05:26 AM
- Tagged Is it possible to join a polygon to several sub sets within it? on ArcGIS Desktop Deutschland Questions. 02-21-2017 05:26 AM
- Posted Re: How do i clip a raster data to produce a smooth edge on Mapping Questions. 02-21-2017 05:05 AM
- Posted How do i get the content of my attribute table back? on New to GIS Questions. 02-21-2017 04:59 AM
- Tagged How do i get the content of my attribute table back? on New to GIS Questions. 02-21-2017 04:59 AM
- Posted Re: How do i clip a raster data to produce a smooth edge on Mapping Questions. 01-25-2017 03:21 PM
- Posted How do i clip a raster data to produce a smooth edge on Mapping Questions. 01-25-2017 01:19 PM
- Tagged How do i clip a raster data to produce a smooth edge on Mapping Questions. 01-25-2017 01:19 PM
- Posted Re: How do i expand data display range in a map in ArcGIS on Coordinate Reference Systems Questions. 05-02-2016 03:17 PM
- Posted Re: How do i expand data display range in a map in ArcGIS on Coordinate Reference Systems Questions. 05-01-2016 09:40 AM
- Posted Re: How do i expand data display range in a map in ArcGIS on Coordinate Reference Systems Questions. 05-01-2016 09:35 AM
- Posted How do i expand data display range in a map in ArcGIS on Coordinate Reference Systems Questions. 04-30-2016 02:33 PM
- Tagged How do i expand data display range in a map in ArcGIS on Coordinate Reference Systems Questions. 04-30-2016 02:33 PM
- Kudoed Re: Using the Raster calculator to determine slope length for DanPatterson_Retired. 04-13-2016 06:20 AM
- Posted Re: Using the Raster calculator to determine slope length on Coordinate Reference Systems Questions. 04-12-2016 06:56 PM
- Posted Re: Using the Raster calculator to determine slope length on Coordinate Reference Systems Questions. 04-12-2016 06:42 PM
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