In computing the velocity and time of the flow path, the slope is needed but their are values in its field that are zero. so, how can I replace those zero values into 0.0001 so that the output of the computation will not be zero.
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replacing zero values of the field using arcmap
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Dissolving points based on easting and northing with statistic type first as aggregate function using PostGIS?
I have two points features having point_ID, Easting and Northing fields and want to dissolve based on Easting and Northing with statistic type aggregate as “first” for point_ID, as you do in ArcMap.
How can I achieve this using PostGIS?
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Time series animation problem
How to create time series animation with unequal time interval in the data in ArcGIS? for eg I have population data for the years 2013,2012,2010,2004,1990,1950,1900, so how can I create time series animation with this kind of unequal time interval?
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How to extract information from several shapefiles in the same time?
I’m using ArcGIS 10.2.1. I have a shapefile for 10 catchments and other three shapefiles for landuse, soil type and rock types. To extract the area of land use types, soil types or rock types for each catchment, I used Tabulate intersection.
However, Tabulate Intersection helps me to extract information from one shapefile only at a time (e.g. either soil type or land use type). I want to extract information from the three shapefiles in the same time.
I want to get the area of combination of land use, soil type and rock type in the same time.
The output I’d like to get should look like the table below
Any idea how can I do this in ArcMap would be appreciated?
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Is there a way to change the orientation of all text labels at once?
I rotated my extent -45 degree to make it look better. Problem is all the labels that I converted to graphics so I could rearrange them are also at -45 degrees. Any way to change that easily?
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Unable to select ArcGIS layout boxes (created with Insert Picture) after path changed?
I inserted a few png images into my map layout (state road shields), but when I changed the path for the folder they were located in, they no longer appear. The problem is that a box has appeared that is not selectable, and I cannot delete it.
Attached is a picture showing two yellow boxes “481px-Florida_281.svg”. Is there a way to remove these. I have re-added the images to the map, but the box still remains.
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Arcscan greyed out
the Arcscan toolbar is greyed out.
- The Arcscan extension is enabled.
- The raster is a “bi-level” image
- There is an editable polyline layer in the ArcMap TOC
Do you have any idea why i still can’t use ArcScan?
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Using CURRENT_DATE function on ArcSDE SQL Server Database?
I am writing a script to access data from each day. I would like to select by attribute and send these features to a local file geodatabase. After reading some documenation, CURRENT_DATE is the function which reads data for today.
This is an example of my data ’2015-02-02 00:00:00′. I don’t have the time for any features, so in reality it is only YYYY-MM-DD. In a local file geodatabase, the query
PlannedDate = CURRENT_DATE works. However in my ArcSDE SQL Server connection it does not.
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Widening Multiple Polygons at same time in ArcMap?
I am trying to edit polygons in the same feature class. I have a feature class which contain a number of polygons. I will need to increase the size of the polygons but only the width (the length has to remain). The polygons are not perfect rectangles thus making it a bit harder to edit as well.
I am wondering if I can do this using geoprocessing tools or DIE to edit the polygons at the sametime thus I do not have to edit the polygons one by one. I have quite a number of polygons to edit. If I have a tool to run or something the results will be more consistent compared to editing by hard.
Or I am wondering if it is possible to add a polygon on top of the original polygon with the same length but larger width.
Example:
The edited polygon should look like this:
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Can Compound Topographic Index (CTI) / Topographic Wetness Index (TWI) produce negative values?
I am calculating Topographic Wetness Index for a study area using SRTM DEM (90 and 30m).
I’ve seen several versions of TWI (CTI).
I have been using: TWI = ln(As +1 / tanB)
where As = catchment area, B = slope (degrees/radians??)
When I run this function, the output contains negative values (using slope in degrees and radians).
Are negative values acceptable? Or does this indicate an error in the analysis??
I understand the output should be scaled to 1-10, but negative values seems counter intuitive. Could someone explain what negative values could mean (due to flat areas, no data values?)
On a side not, the calculations are being run on on a very large area, which overaps several watersheds. Is it appropriate to run TWI over such a large extent?
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How to Calculate Field in joined table using ArcPy?
I have to calculate a field based on another field in a joined table, but an error occurs:
“Parameters are not valid.
ERROR 000728: Field !Table_A.field_A! does not exist within table”
My code:
import arcpy
from arcpy import env
env.workspace = "C:/TMP/BASELINE.gdb"
Table_A = "dist"
Table_B= "matrix"
arcpy.AddJoin_management(Table_A, "id_grid", Table_B, "id_matrix")
arcpy.CalculateField_management(Table_A, "!" + Table_A + ".field_A!", "!" + Table_B + ".field_B!","PYTHON")
Both tables are in the BASELINE.gdb. The Join occurs without any problem.
I forgot to say that, of course, “field_A” exists in “Table_A” and “field_B” exists in “Table_B”.
Last but not least, if I run the same calculation in ArcMap, using Field Calculator, no error occurs.
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Combining rows in an attribute table based on field
I am using ArcMap 10.2.2 on a Windows 7 PC.
I have shapefile range data for multiple species (multiple species in one layer), and this range data is accompanied by information relevant to the species.
Some of the species I am working with have discontiguous geographic ranges. If species X has three disconnected places it lives, I have three different rows in my attribute table, with lots of redundant data (i.e. there are three rows with identical information EXCEPT the information that relates to the polygon size). Because of this, I have about 3,300 rows for ~250 species.
I would like ArcMap to combine rows based on the species, but I can’t seem to figure out how to do this properly.
I’ve tried dissolving based on the species name field (with multipart features), but when I do this, I just get a new layer with nothing in it.
Any suggestions?
I’ve tried all the things suggested in How to combine rows in attribute table using ArcGIS for Desktop? but none seem to be working.
ETA: Posted these in a comment, but here are some relevant screenshots:
My intended output would be for all of the highlighted rows in the first screenshot to become a single row. And I would like that done for all ~250 species.
What I’m getting when I use dissolve:
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Can you re number representations in arcmap?
I created a representation and added loaded rule or import symbols but had to delete some. Now the numbers in front of the name of the rule is out of order ( [2],[3],[5],[7]). I know you can change the name of the rule but I was wondering if there is a way to change this rule id number in front of the name?
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Delete custom toolbar grayed out in ArcGIS 10.2
Recently I worked on adding a custom toolbar to ArcMap. It took a few tries, and now there are my initial ‘drafts’ of the toolbar still added to my ArcMap list of toolbars. According to the help, I should just be able to delete them. However, the Delete button is grayed out when I try to select my custom toolbar, as if it were one of the default toolbars. Has anyone else had this problem and come up with a solution?
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Is there a QGIS alternative for ArcMap's Append (to Shapefile) Data management tool?
Is there something out there for QGIS that is similar to the Append Tool in ArcMap?
Reason I am looking:
I am currently working on a storm drainage project that involves GPSing Storm drain lids.
My issue is when I capture the points with the GPS unit, and then bring them into the office. The GPS unit produces a CSV file for me to import into QGIS. It gives the CSV file with generic header names ( field1, field2, field3..etc) This is fine, until I try to copy it into the working shapefile that has all the other storm drains.
The beautiful thing with Arcmap’s append tool was that I could map each field from my csv file to the destination shape file…ex… “field1″ from csv is equal to “Elevation” field in my shapefile. And thus update my shapefile with the newest points.
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How to find soil names for “mukey” in USDA Soil Data SSURGO
I an trying to join the soil descriptions in the tabular data to the spatial data in ArcGIS. I have both the mukey and musym in the attribute table associated with my soil polygon layer in my map. When I go into the tabular data in my geodatabase, there is no data inside any of the files.
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Adding a layer can sometimes load raster footprint!
Just trying to refine my ArcObjects code to add a layer into ArcMap based on passing the fully quailified (String) name of the layer – problem is, if it’s a raster, it will load in the vector footprint of the raster which is no good. I want to load the raster in, not it’s footprint.
I can’t see anything obvious that allows you to test for rasterness, other than swapping the test in my code around – i.e testing for raster first then vector. Is there anything I am missing, is there a more elegant code out there to achieve this?
CODE
public static ILayer GetLayerFromSourceName(String name)
{
ILayer esriLayer = null;
IWorkspace2 wsp2 = (IWorkspace2)Workspace;
try
{
if (wsp2.get_NameExists(esriDatasetType.esriDTFeatureClass, name))
{
IFeatureLayer featureLayer = new FeatureLayerClass();
featureLayer.FeatureClass = GeodatabaseManager.FeatureWorkspace.OpenFeatureClass(name);
esriLayer = (ILayer)featureLayer;
}
else if (wsp2.get_NameExists(esriDatasetType.esriDTRasterDataset, name) ||
wsp2.get_NameExists(esriDatasetType.esriDTRasterCatalog, name))
{
//This works only for remote raster datasests.
IRasterDataset rasterDataset = null;
IRasterLayer rasterLayer = new RasterLayerClass();
rasterDataset = RasterWorkapaceEx.OpenRasterDataset(name);
rasterLayer.CreateFromDataset(rasterDataset);
esriLayer = (ILayer)rasterLayer;
}
}
catch (Exception ex)
{
Debug.WriteLine(ex.Message);
}
return esriLayer;
}
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Pasting Point goemetry with Z and M values to Simple Point Geometry
This should be kind of easy but I’m looking for a best practice scenario. I just tried adding 14 points from a point shapefile into another layer in our ArcSDE database. I assumed the layer in SDE was also a point file since it displays as such. I got an error saying there were no files with the appropriate geometry to paste into. I looked and the geometry type of the SDE layer is listed as “Point” but the feature type is “Simple”. I inherited this database so I don’t know how the layer was created. Is this “simple” geometry something like an event theme (e.g. was it likely just created from a spreadsheet?)?
More importantly, how should I proceed to get the new points from my shapefile into this “Simple geometry” layer?
I also learned just now that the input shapefile has z and m values so I’m exploring stripping those off using “Environment Settings” and the “Copy Features” too.
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select by location in vba
I got two Layers (Point and polygons) in my Application and want to write a vb macro, where point layer is cities layer and polygon layer is state’s layer, I want to know that how many cities are inside state’s layer
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AVHRR Max NDVI product
I’m trying to take a max annual NDVI product derived from AVHRR and relate it to a specific area that I’m examining.This requires me to identify the region of interest based on Landsat scenes, and relate it to AVHRR’s raster resolution. I know what area I want to look at in the Landsat scenes, but am having trouble translating it to area in AVHRR, which is currently projected in North Pole Lambert Azimuth Equal Area.
My landsat layer is currently projected in UTM Zone 13N.
I have tried switching both projections to something compatible, with each to USA Contigous Lambert Conformal Conic, but there still seems to be a fundamental projection issue occurring. The region of interest is in NM, and it doesn’t appear the AVHRR scene is lining up as shown:
The basemap is projecting in WGS84, and it appears as though the reprojected landsat scene conforms with the baseman, whereas the AVHRR scene does not.
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