Tagged Questions

1
vote
4answers
164 views

Counting road intersections and blocks

I have a shp file that consists of the road system of Mexico City. I would like to count the number of road intersections (crossings) and blocks (which I would define as a segment starting from one ...
1
vote
1answer
52 views

Determining Pixel-by-pixel Catchments in ArcHydro

I used ArcHYDRO to prepare HydroDEM (5m) without sinks, Flow direction (FDR) raster, flow accumulation raster (FAC). As I understand FAC, value of pixel shows number of pixels that contribute to this ...
3
votes
0answers
90 views

Draw two separate lines from A to B and B to A

I have an Origin-Destination table like this Origin Destination Value A B 10 B A 100 A C 120 ... For all the locations A, B, C... I have another table indicating their location (Lat and Lon) Is ...
4
votes
2answers
219 views

How do I read a File Geodatabase using R?

File geodatabase (fgdb) includes numerous file geodatabase tables. As far as I know they exist as dbf files, but are within a Database.gdb. In ArcCatalog, the file pathway resembles ...
0
votes
2answers
47 views

Reversing a “combine” function on a raster

I have a raster that I think was "combined" using an arcmap function. I am wondering if there is a way to extract just one raster layer from the combined dataset in order to use it separately, either ...
2
votes
1answer
185 views

Inverse distance weighted interpolation for categorical and/or binary datasets

I want to perform an Inverse distance weighted (IDW) interpolation to a series of points. However my data set can be categorical or binary and just like the IDW I want to interpolate the new values ...
7
votes
2answers
172 views

How to create a solar intensity map for a garden plot?

I'm interested in creating a raster surface that depicts the average solar intensity per unit area for a small garden plot. I imagine the inputs into the model would be the following: Plot ...
4
votes
0answers
41 views

ArcGis Raster Resampling Question [duplicate]

Possible Duplicate: How do you decide what interpolation method to use for resampling raster data? I want to interpolate a certiain target variable over a large territory. I trained a ...
4
votes
1answer
98 views

How to stack rasters for ecological analysis?

The attached image shows two different forest openings. Each opening has the following layers associated with it: Point shapefile 1 = A red X which represent a large "legacy" tree in the gap Point ...
3
votes
2answers
132 views

Reproduce raster with the same extent, and the same number of columns and rows

I have two raster A and B. A and B have the same grid size but different extent. How can I make A has the same number of columns and rows, as well as the spatial extent of B?
5
votes
2answers
379 views

How to implement bivariate Ripley's K function in ArcGIS 10?

The attached image shows a forest gap with red pine represented as circles and white pine represented as crosses. I am interested in determining if there is a positive or negative association between ...
-1
votes
1answer
128 views

Exporting Grid from R to use it in ArcGIS

i want to export a grid from R into format readable by ArcGIS. how can i do so? jones
12
votes
3answers
274 views

How to determine if trees within forest gaps are clustered?

The attached dataset shows approximately 6000 saplings in approximately 50 variable sized forest gaps. I am interested in learning how these saplings are growing within their respective gaps (i.e. ...
5
votes
1answer
159 views

Stats on individual grid points nearest neighbours

First, thank you for this extremely useful and easy-to-access forum! I have shp of points where each point is the centroid of the individual cells of a 1*1km grid (~ 500 000 points). For each of ...
12
votes
2answers
476 views

Raster noise reduction and edge smoothing

I have a raster image like this I want to delete the isolated noise point and smooth the edge (say the white single points, and I want the edges of the entity look smooth). How can I do this in ...
6
votes
3answers
1k views

How to find and merge duplicate points?

I have two point shapefiles: Red and Blue. Each point shapefile has a z value which represents a radius (i.e. represented as buffers in the example). A duplicate point is defined as a point that ...
5
votes
2answers
232 views

Using rpy2 in ArcGIS

I have a 3rd party python geoprocessing script that requires rpy2, and thus also r. What is the best way to get these working together? Using R with ArcGIS Desktop says the most useful option for ...
14
votes
3answers
506 views

Ecological geospatial conundrum

I am looking for a different, more elegant solution to a spatial statistics problem. Raw data consists of an x-y coordinate for each individual tree (i.e. converted to a point .shp file). Although ...
3
votes
1answer
250 views

Spatial Interpolation Methods like PRISM

I am looking for some kind of software (free software) that allows me to make an interpolation like PRISM software. The interpolation used in PRISM is a local regression and accounts for ...
2
votes
1answer
175 views

Generic comparison for kriging in geoR and ArcGIS

I am going to do a project based on kriging. The targeted area would be as big as United States and my grid would be 10km*10km. I am wondering the differences of efficiencies for the methods ...
3
votes
4answers
659 views

relationship between sp package in R; mapwindow; ArcGIS/Quantum GIS

I am using ArcGIS at office for some visualization work, but I feel it kinda dump to performing the same tasks several times for visualizing some data on different maps. I am think of automating it ...
7
votes
3answers
447 views

How can I make a county-level shape file from a set of points at 30 x30 km spacing?

I have a data set in csv form, like: latitude, longitude, value -45, 45, 10 .... I would like to calculate county level means from these data, using either ArcGIS or R+grass. I have the ArcGIS USA ...
3
votes
1answer
2k views

Convert a shapefile with northing/easting to ASCII raster with latitude/longitude

Linked below is a polygon shapefile whose projection is NAD83 and whose values are LU/LC codes. Coordinates are meters of northing and easting. I would like to convert it to an ASCII raster with ...
14
votes
3answers
2k views

R to ArcGIS 9.3.1 or 10

I m trying to learn R generally and making statistics for maps. I found some useful tricks for making maps with it but it is not the best you can do. My everyday GIS program is ArcGIS. How I can use ...
10
votes
1answer
2k views

Using R with ArcGIS Desktop

In response to comments below, a re-phrasing of the question. I've used the integration of R with QGIS, and found it a very uesful tool. Having taken a look at the R toolbox extension for 9 and the ...