search for: regrid

summary: spatial data to be input to a regional-scale environmental model must (1) be converted to netCDF and then (2) "regridded" (cropped, projected, increased resolution). In a public git repository https://github.com/TomRoche/GEIA_to_NetCDF I have R code (with bash drivers) that does the conversion step, and plots the converted output, apparently correctly. However attempts to plot the output of the regridding s...

Hello R Users, I am new to R. I have two data sets i) TOMS aerosol optical depth(AOD) and ii) TOMS ozone(O3). > > AOD data is on 1x1 grid and O3 data is on 5x5 grid. > > First I want to read AOD and O3 as it is and then I want to regrid AOD on > 5x5 grid as O3. > > Reading is first problem. > > FIRST PROBLEM READING AOD: > > AOD data is in following format: > > ######### > Latitute: 89.5 > 167 0 0 0 0 0 182 0 0 0 0 0 0 0 0 0 0 0 0 200 0 0 0 0 0 0 > 0 0 0 0 0 0 0 0 0 0 0 0 0 0 155 0 0 0 0 0 156...

Hello R Users, I have two data sets i) TOMS aerosol optical depth(AOD) and ii) TOMS ozone(O3). AOD data is on 1x1 grid and O3 data is on 5x5 grid. First I want to read AOD and O3 as it is and then I want to regrid AOD on 5x5 grid as O3. Reading is first problem. FIRST PROBLEM READING AOD: AOD data is in following format: ######### Latitute: 89.5 167 0 0 0 0 0 182 0 0 0 0 0 0 0 0 0 0 0 0 200 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 155 0 0 0 0 0 156 0 0 0 0 0 0 ............ ........... Latitude: 88.5 ......

Dear all, I have a grid (data frame) dataset at 0.5 x 0.5 degrees spatial resolution (720 columns x 360 rows; regular spacing) and wish to coarsen this to a resolution of 2.5 x 2.5 degrees. A simple calculation which takes the mean of a block of points to form the regridded values would do the trick. Values which should be excluded from the calculation are -9999 (unless all points within a block are -9999, in which case -9999 should be returned as the 'new' cell). How would I go about achieving this in R? Any help or guidelines would be very much apprecia...

...for this is: a <- rep(1,100)+rnorm(100) b <- rep(2,100)+rnorm(100) c <- rep(1.5,100)+rnorm(100) n.start <- 50 coefs <- array(NA,c(51,4)) for (i in (n.start:100)) coefs[i-n.start+1,] <- coef(lm(a ~ b + c, subset=1:i)) I want to avoid loops, so I was trying to make something like: regride <- function(formula,dat,sub,w) { window <- c(1:sub) w[1:sub-1] <- w[1:sub-1]*beta^sub coefs(lm(formula=formula,data=dat,subset=window,weights=w)) } coefs <- sapply(n_start:dim(ind)[1],regride,formula,dat,x) But it's not working. Best regards, Caio Casimiro -- Caio R...

...help a bit. However, I am a neophyte (as you may see from the code below) and did not find a way by now. I would appreciate very much any suggestions for speeding up the procedure. Thanks, Zarza The code (running but sloooooow): ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ regrid <- function (infolder, x, outfolder) { # List of input files setwd (infolder) filelist <- dir (pattern=".*.asc$", full.names = F) # Dimensions (making use of the header information coming with # the .asc-input files, ESRI-format) hd <- read.table (filelist [1], nrows = 6) cols...

SUMMARY: Specific problem: I'm regridding biomass-burning emissions from a global/unprojected inventory to a regional projection (LCC over North America). I need to have boundaries for Canada, Mexico, and US (including US states), but also Caribbean and Atlantic nations (notably the Bahamas). I would also like to add Canadian provinces...

...on seems to be returning a clean integers to serve as inputs for the creation of the 'positions' variable, for whatever reason R doesn't read it that way. I would be very grateful for any advice on how I can either alter my approach entirely (I am sure there is a far more elegant way to regrid data in R) or a simple fix for this rounding error. Many thanks in advance, Aaron -- Aaron Polhamus <aaronpolhamus@gmail.com> Statistical consultant, Revolution Analytics MSc Applied Statistics, The University of Oxford, 2009 838a NW 52nd St, Seattle, WA 98107 Cell: +1 (206) 380.3948 [[a...