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Trying to read a list of maps using readRAST6

3 messages · Edzer Pebesma, Thomas Adams

Original
Thomas Adams
# 
All:

With sp & spgrass6 I have no problem reading a list of maps with 
readRAST6 when I do the following:

data<-readRAST6(c("map1","map2","map3",?))

however, I need to do this dynamically within a script, for example:

 > inputfile<-Sys.getenv("R_INPUT_FILE")
 > map_list<-scan(inputfile,list(""))

Read 21 records

 > map_list

[[1]]
[1] "sref_em.t09z.pgrb212.ctl" "sref_em.t09z.pgrb212.n1"
[3] "sref_em.t09z.pgrb212.n2" "sref_em.t09z.pgrb212.p1"
[5] "sref_em.t09z.pgrb212.p2" "sref_eta.t09z.pgrb212.ctl1"
[7] "sref_eta.t09z.pgrb212.ctl2" "sref_eta.t09z.pgrb212.n1"
[9] "sref_eta.t09z.pgrb212.n2" "sref_eta.t09z.pgrb212.p1"
[11] "sref_eta.t09z.pgrb212.p2" "sref_nmm.t09z.pgrb212.ctl"
[13] "sref_nmm.t09z.pgrb212.n1" "sref_nmm.t09z.pgrb212.n2"
[15] "sref_nmm.t09z.pgrb212.p1" "sref_nmm.t09z.pgrb212.p2"
[17] "sref_rsm.t09z.pgrb212.ctl1" "sref_rsm.t09z.pgrb212.n1"
[19] "sref_rsm.t09z.pgrb212.n2" "sref_rsm.t09z.pgrb212.p1"
[21] "sref_rsm.t09z.pgrb212.p2"


data<-readRAST6(map_list)
spplot(data,?)

What happens is that "map_list" is treated literally, not as: 
data<-readRAST6(c("map1","map2","map3",?)) which works. I have tried a 
number of things, such as:

data<-readRAST6(as.list(map_list))
data<-readRAST6(c(map_list))
data<-readRAST6(as.vector(map_list))
data<-readRAST6(eval(map_list))

How do I do this?

Regards,
Tom
Edzer Pebesma
# 
Thomas, perhaps:

data <- readRAST6(map_list[[1]])

as map_list is a list, and readRAST6 seems to want a character vector,
which is in the first list element of map_list.
Thomas Adams wrote:

  
    

      
      
    

  


  


      

    

    

      
      

        


  

        

      Thomas Adams
    

    

      
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Robert,

My apologies, your suggestion

data<-readRAST6(unlist(map_list))

did work, only I had another error in my scripting that made it appear 
that your suggestion was not working. Thank you so much for your help. 
I'm still very much a novice with most of R!

Regards,
Tom

        
Edzer Pebesma wrote: