[R] locate values to their positions based on their pixel and line in other files

Amen amen.alyaari at Bordeaux.inra.fr
Wed Apr 25 20:14:19 CEST 2012


I have 3 files A ,B ,C as binary files. C represents the values of tepm
measured every 3 hours for one month so it has 674200 columns and 248
rows.values of A represent the correspond lines(these values could be within
1to360) and , while values of B represent the correspond pixel(1to720) for
each point in file C(so both they have 1 row and 67420rows).Now I will
create a new matrix ,M ,which has this dim(360,720).for example the first
value in C it will be represented in the creatd matrix based on the
corspding pixl and lines.assume the first value is 54(row 1 and column 1)in
C so in order to locate it in my new matrix we need to know what its pixl
and line that this point shoud be assocated with ,therfore I need to tell R
that take its pixl value from A and its line from B and locate it in my new
matrix. this is to be done for first row out of 248 rows and write it to new
file then do the same for the second row and write to a new file and so on
for all 248 rows.

 library(Matrix)
 M <- Matrix(-9999, 360, 720)## creat matrix with 720 columns and 360 rows
with valus of -9999
 long <- file("C:\\New folder (5)\\inra.bin", "rb")
  A=readBin(long, integer(), size=2,n=1*67420, signed=TRUE)
    lot <- file("C:\\New folder (5)\\lat.img", "rb")
  B=readBin(lot, integer(), size=2,n=1*67420, signed=TRUE)

   for (i in c(1:67420)) {
   wind <- file("C:\\Wind_WFD_200201.bin", "rb")
C=readBin(wind, integer(), size=2,n=248*67420, signed=TRUE)##it has 67420
columns and 248 rows
    M(A(i),B(i))= C(i)}
I wrote the above code but didn't work.I am so sorry for this long
description and thanks in advance

--
View this message in context: http://r.789695.n4.nabble.com/locate-values-to-their-positions-based-on-their-pixel-and-line-in-other-files-tp4587563p4587563.html
Sent from the R help mailing list archive at Nabble.com.



More information about the R-help mailing list