It's hard to check without a reproducible example, but the following code should give you a 3d array of lat x long x time:
library(reshape) df$lat <- round_any(df$LATITUDE, 5) df$long <- round_any(df$LONGITUDE, 5) df$value <- df$TIME cast(df, lat ~ long ~ time, mean) On Thu, Apr 30, 2009 at 10:55 AM, dxc13 <dx...@health.state.ny.us> wrote: > > Hi all, > I have a data frame that looks like such: > LATITUDE LONGITUDE TEMPERATURE TIME > 36.73 -176.43 58.32 1 > 50.95 90.00 74.39 1 > -30.42 5.45 23.26 1 > 15.81 -109.31 52.44 1 > -80.75 -144.95 66.19 2 > 90.00 100.55 37.50 2 > 65.41 -4.49 29.83 2 > > and this goes on for a A LOT more records, until time=1200 > > I want to create a 5 degree by 5 degree grid of this data, with the value of > temperature in the appropriate grid cell. I want one grid for each time > value. For each time value, this works out to be a 36x72 grid with 2592 > cells because the longitude spans -180 to 180 and latitude spans 90 to -90 > and they would be in increments of 5 degrees. If there are no temperatures > available to be put into a grid cell, than that cell should get a missing > value, NA, put into it. > Also, could the gridded result for each time be written to a text file > before processing the next time value? > > Hope this is clear. > Thanks in advance. > > dxc13 > -- > View this message in context: > http://www.nabble.com/gridding-values-in-a-data-frame-tp23319190p23319190.html > Sent from the R help mailing list archive at Nabble.com. > > ______________________________________________ > 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. > -- http://had.co.nz/ ______________________________________________ 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.
