Re: working with multiple csv file.

HI Sangeeta,

'addfiles', like 'addfile' only works for supported formats -- not for ascii text files. You will need to use asciiread in a loop to read each file in succession.
It will be easier to create a variable that contains all the values for a month's worth of data if you calculate how many elements you need in advance.
For January you could do something like this:

       dir="/root/Desktop/filecsv/"
       files=systemfunc("ls "+dir+"Air*")
       fieldx = new(24 * 31, float)

       do i = 0, dimsizes(files) - 1
             data = asciiread(files(i),-1,"string") ; or use data := asciiread(files(i),-1,"string"
             fieldx(i*24:(i+1)*24 - 1) = stringtofloat(str_get_field(data(1:24),x,","))
             ; etc. for each field you want
             delete(data)
      end do

      ; process each field as needed

This assumes the "ls" command is only getting a month's worth of data. If you are going to do more than a month's worth you will need an outer loop and
the code will need to be elaborated.
This code has not been tested. It is only a suggestion of how to proceed.
 -dave

On Aug 6, 2013, at 10:32 PM, sangeeta maharjan <sangeetamaharjan@gmail.com> wrote:

> Dear NCL Users,
> I was able to read a csv file containing hourly air remperature data
> of a day using following code.
>
> begin
> filename="/root/Desktop/AirTemperature(1).csv"
> data=asciiread(filename,-1,"string")
> delim=","
>
> tfs=str_fields_count(data,delim)
>
> field1 = (str_get_field(data(1:24),1,","))
> field2 = (str_get_field(data(1:24),2,","))
> field3 = stringtofloat(str_get_field(data(1:24),3,","))
> field4 = stringtofloat(str_get_field(data(1:24),4,","))
> field5 = stringtofloat(str_get_field(data(1:24),5,","))
>
>
> print ("Date="+field1+" time="+field2+" Min="+field3 +"
> Max="+field4+" Avg="+field5)
>
> end
>
> But, I need to calculate the monthly average on air temperature for
> which I have to read multiple csv files. I wrote couple of codes which
> are as follows but it didn't work.
>
> begin
> dir="/root/Desktop/filecsv/"
> files=systemfunc("ls "+dir+"Air*")
> print(files)
> printVarSummary(files)
> print(files(0))
>
> f = addfiles (files, "r")
>
> ListSetType (f, "cat")
> data=asciiread(f,-1,"string")
> delim=","
>
> end
>
> Can you please help me to work with multiple csv file ?. For your kind
> reference, I have attached one of my csv file herewith.
>
> Thanks & Regards,
> Sangeeta Maharjan.
> <Air Temperature (1).csv>_______________________________________________
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Received on Wed Aug 7 12:38:21 2013