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Help in modifying code to extract data from url

4 messages · Bhaskar Mitra, Jim Lemon, Richard O'Keefe +1 more

Original
Bhaskar Mitra
# 
Hello Everyone,

I am trying to extract data from a url. The codes work well when the
data structure is as follows:

X Y
1 2
1 5
1 6
1 7
3 4

However, the code fails when the data structure has no number
under the 2nd column (shown below).I get the following error:

"Error in data.frame(..., check.names = FALSE) :
  arguments imply differing number of rows: 242, 241"


X Y
1 2
1
1
1 7
3 4

Can anyone please help me in how I can modify the codes ( shown below) to
adjust for the above mentioned condition
in the data structure.

library(rjson)

url <- "abcd.com"
json_data <- fromJSON(file= url)
d3 <- lapply(json_data[[2]], function(x) c(x["data"]))
d3 <- do.call(rbind, d3)
X_Dataframe = as.data.frame(unlist(d3[[1]]))
b <- do.call("cbind", split(X_Dataframe, rep(c(1, 2), length.out =
nrow(X_Dataframe))))


regards,
bhaskar
Jim Lemon
# 
Hi Bhaskar,
If you are using read.table or similar, see the "fill=" argument.

Jim
On Thu, May 20, 2021 at 9:54 AM Bhaskar Mitra <bhaskar.kolkata at gmail.com> wrote:
2 days later
Richard O'Keefe
# 
The source being a URL is not important.
The important things are
 - what the structure of the JSON data is
 - what the MEANING of the JSON data is
 - what that meaning says about what SHOULD appear in the data
   from in these cases.
Arguably this isn't even an R question at all.  It's a question about your
data.
Since you have replaced the actual URL with a dummy (example.com is the
traditional
never-to-be-in-use host name), we cannot even guess these things by looking
at the
data ourselves.


On Thu, 20 May 2021 at 11:54, Bhaskar Mitra <bhaskar.kolkata at gmail.com>
wrote:

  
  


  


      

    

    

      
      

        


  

        

      David Winsemius
    

    

      
      #
    

  


  

      
Several authors hav addressed this problem with names that resemble 
"rbindfill". In my machine I find four instances:

??rbindfill

Help pages:
ffbase::ffdfrbind.fill??? ??? rbind for ffdf where missing columns are 
added if not available in one of the ffdf objects
plyr::rbind.fill??? ??? Combine data.frames by row, filling in missing 
columns.
plyr::rbind.fill.matrix??? ??? Bind matrices by row, and fill missing 
columns with NA.
rockchalk::rbindFill??? ??? Stack together data frames