Dear Pascal, Thanks for your reply. From your answer I perceived that if followings are first three elements of a file > dput(ccc[1:3]) c(0.15912090241909, 0.167244642972946, 0.192471280694008) then 0.15912090241909 is precipitation magnitude , 0.167244642972946 is RSTN and 0.192471280694008 is flag value.Did i get it right? Eliza > From: kridox@ymail.com > Date: Thu, 27 Mar 2014 12:39:30 +0900 > Subject: Re: [R] reading dataset > To: eliza_botto@hotmail.com > CC: r-help@r-project.org > > Hello, > > Some hints: > - for the year 1961, the total number of values is 27594000, > - there are 180 longitudes and 140 latitudes, > - there are 365 days, > - there are 3 variables, > > Compare the total number of values and the result of (180 x 140 x 365 x 3). > > The order is "precip", "rstn", "flag", "precip", "rstn", "flag", > "precip", "rstn", "flag"... > > Hope this helps, > Pascal > > On Thu, Mar 27, 2014 at 9:45 AM, eliza botto wrote: > > Dear useRs, > > A similar question has previously been asked by another user (https://stat.ethz.ch/pipermail/r-sig-geo/2011-September/012791.html) but i'll try to discuss it from another angle. Its about data reading. I am trying to read to read a data-set APHRO_MA_050deg_V1101R2.1961.gz from http://www.chikyu.ac.jp/precip/cgi-bin/aphrodite/script/aphrodite_cgi.cgi/download?file=%2FV1101R2%2FAPHRO_MA%2F050deg. > > I copied the command from previous post which is > > ccc <-readBin("APHRO_MA_050deg_V1101R2.1961", numeric(), n=1e8, size=4, signed=TRUE, endian='little') > > Followings are what I know about the structure of data set. The file contains daily fields for 365 days. These daily fields are arranged according to the Julian calendar. Daily > > fields (data arrays) contain information on the precipitation amount and > > ratio of 0.05-degree cells containing a rain gauge. In the case the given file which is a > > 0.5-degree grid file, each field consists of a data array with longitude > > by latitude dimensions of 180 x 140 elements for APHRO_MA. > > The first element is a cell at the southwest corner centered at [60.25E, 14.75S], the second > > is a cell at [60.75E, 14.75S], ..., the 180th is a cell at [149.75E, > > 14.75S], and the 181st is a cell at [60.25E, 14.25S]. The data files are written in PLAIN DIRECT ACCESS BINARY. In each daily field, the array for precipitation comes first, followed by > > information on the rain gauge. Each element (both precipitation and > > rain gauge information) is written as a 4-byte floating-point number > > in little endian byte order. Users should swap the byte order to > > big endian if necessary. There are no 'space', 'end of record', or > > 'end of file' marks in between. As it says that precipitation data is in the form of array which comes first, followed by the information on rain gauge, how do I know which element is precipitation data and which is the information of the rain gauge?Thankyou very much in advance > > > > Eliza > > [[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. > > > > -- > Pascal Oettli > Project Scientist > JAMSTEC > Yokohama, Japan [[alternative HTML version deleted]]