Hello, I did a mistake in my script:
> hour <- day*24; hour <- c(hour[1],cumsum(hour[1:length(hour)-1])) should be replaced by: > hour <- day*24; hour <- c(0,cumsum(hour[1:length(hour)-1])) Regards Le 05/07/2012 10:49, Pascal Oettli a écrit :
Hello, A short code to include real monthly calendar to your data, similar to the one inside NCEP2 reanalysis. library(ncdf) lon <- seq(from=140.0251, to=146.6751, length.out=241) lat <- seq(from=-38.975, to=-31.025, length.out=160) x=dim.def.ncdf("Lon","degreesE",as.double(lon)) y=dim.def.ncdf("Lat","degreesN",as.double(lat)) y1 = 1800 # start of the period y2 = 2012 # end of the period year <- seq(y1,y2,1) day <- c(31,28,31,30,31,30,31,31,30,31,30,31)%*%matrix(1,1,length(year)); day[2,leap.year(year)] <- 29; day <- as.vector(day) hour <- day*24; hour <- c(hour[1],cumsum(hour[1:length(hour)-1])) year <- rep(year,each=12) syntime <- hour[year==1968] #change the year or change this line to include more years t=dim.def.ncdf("Time","hours since 1800-1-1 00:00:00",syntime,unlim=TRUE) And your "mrain" matrix should have 3 dimensions (lon x lat x time), before to save it as a NetCDF file. Regards. Le 04/07/2012 23:13, Jun Chen a écrit :Hi Pascal, I think I figure it out. By doing the following, I can made "lon" & "lat" become a class of dim.ncdf: lon <- seq(from=140.0251, to=146.6751, length.out=241) lat <- seq(from=-38.975, to=-31.025, length.out=160) x=dim.def.ncdf("Lon","degreesE",as.double(lon)) y=dim.def.ncdf("Lat","degreesN",as.double(lat)) However, after running the script, there is a error I really unable to understand: error at data.frame(..., check.names = FALSE) : parameter value mean different rows 0, 31981 If you can understand what the problem is, please as kind as offer me a direction. Many thanks, JunDate: Wed, 4 Jul 2012 10:39:29 +0100 From: kri...@ymail.com Subject: Re: [R] Please help To: chensh...@hotmail.com CC: r-help@r-project.org Hello, Following lines are wrong:x=dim.def.ncdf("Lon","degreesE",140.0251:146.6751) y=dim.def.ncdf("Lat","degreesN",(-31.025):(-38.975))You have 241 longitudes and 160 latitudes. lon <- seq(from=140.0251, to=146.6751, length.out=241) lat <- seq(from=-38.975, to=-31.025, length.out=160) Regards ----- Mail original ----- De : Jun Chen <chensh...@hotmail.com> À : r-help@r-project.org Cc : Envoyé le : Mercredi 4 juillet 2012 10h52 Objet : [R] Please help Dear All, I am a research student in environment. I have only little programming knowledge. I am currently doing the last project about rainfall impact on ground water quality in an area. It happens that I have to use R to read rainfall data (3 dimension) from ASC file (*.asc), and then write them into one NCDF file (*.nc). I have been working very hard on study R, but I still can not fix the problem. Could someone please as kind as point out that what the problems are in my R script? Firstly, this is an example of data in asc file: NCOLS 241 NROWS 160 XLLCORNER 140.00012207031 YLLCORNER -39.000000000000 CELLSIZE 0.50000000000000E-01 NODATA_VALUE -99.00000 166.30 160.87 155.23 149.33 143.83 138.52 133.29 128.34 123.76 119.21 115.06 110.90 107.22 103.69 100.40 97.29 94.58 92.15 90.00 87.91 86.20 84.57 83.22 81.94 81.11 80.38 79.37 78.73 79.70 79.62 ----------------------------------------------------------------------------------------------------------------------- And then this is the script I wrote: setwd("E:/grid") #defining dimension x=dim.def.ncdf("Lon","degreesE",140.0251:146.6751) y=dim.def.ncdf("Lat","degreesN",(-31.025):(-38.975)) t=dim.def.ncdf("Time","1968-01",1:12,unlim=TRUE) #setup variable varmr=var.def.ncdf("mr","mm",list(x,y,t),-99.00, longname="monthly rainfall") #create ncdf file ncnew=create.ncdf("rainfall.nc", varmr) #read input files=list.files(pattern=".asc") mrain=matrix(0:0,0,3) for(i in files) {rainfall=data.frame(readAsciiGrid(i)) mrain=cbind(mrain,rainfall) } put.var.ncdf(ncnew, mrain) close.ncdf(ncnew) ------------------------------------------------------------------------------- [[elided Hotmail spam]] Many thanks, Jun [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
