185 reputation
29
bio website
location Lund, Sweden
age 46
visits member for 3 years
seen Jun 11 at 10:25

Apr
25
comment What are the units of the calculated area from a raster in decimal degree
Obviously, the projection of the map will then effect the area calculation at such a large spatial extent as Asia. In this case can someone recommend a projection that will give a meaningful calculation of area recognizing this limitation?
Feb
16
comment Estimating cline width at multiple points along a trait gradient
I read your proposal and it seems very practical. How do I learn to do your method? I use ArcGIS 10 with all the plugins and I use R.
Jan
27
comment Where can I find decadal climate and ocean data for Europe?
Thanks for the source for a lot of useful GIS data. Unfortunately, I was unable to locate the data I am interested in, i.e. decade format.
Sep
3
comment query raster in ArcGIS 10
I do not find the help useful at all unfortunately. I try setting an exclusion range, but do not get the intended results. Not sure what else I can do with this tool.
Aug
23
comment How to convert shapefile labels to graphics (in ArcMap 10)?
I do not have Maplex.
Aug
23
comment How to convert shapefile labels to graphics (in ArcMap 10)?
Does it matter whether the annotation is stored in the database or the map?
May
10
comment Calculate the distance between two contours
looks interesting, my trait data is continuous and values have six decimal places. I am interested in these statistics for 0.1 intervals. Any ideas?
May
10
comment Calculate the distance between two contours
That is a good idea, conceptually, but I am unclear if the zonal mean is actually what I need. The contours are over 1000 km long and I would like to know the mean, min and max as these are not elevation, but trait frequency contours.
May
4
comment Estimating cline width at multiple points along a trait gradient
Yes, I have a grid approximating the allele frequency cline generated using ordinary kriging from 134 sites across Fennoscandinavia.
May
4
comment Estimating cline width at multiple points along a trait gradient
The allele cline is a continuous surface and you are absolutely correct that measuring the widths between curves would be ideal. I had searched the literature and could not find a way to do just what you described, so I thought my alternative method would be the best way to demonstrate the heterogeneity of the cline surface. In hybrid zone theory it is traditional to calculate the wdith of the cline as the distance between to 0.22 and 0.78 frequencies. Yes, I mean a straight unbroken line (i.e. no bend at the point).
May
4
comment clip polygon with the extents of contour polylines
I figured that out! Thanks.