Use this procedure to close an EVF. After you open or create an EVF, it is important that you close it using this procedure, to help conserve the IDL session’s memory.

Syntax

---

ENVI_EVF_CLOSE, EVF_ID

Arguments

---

EVF_ID

This is the EVF ID of the EVF to close. The EVF ID is returned from either ENVI_EVF_OPEN (for existing EVF files) or ENVI_EVF_DEFINE_CLOSE (for newly created EVF files).

Example

PRO PRINT_EVF_RECORD_INFO

  compile_opt IDL2

  ;

  ; Open the EVF file can_v1.evf in the

  ; ENVI_Install_Directory/data/vector

  ;

  evf_fname = 'can_v1.evf'

  evf_id = envi_evf_open(evf_fname)

  ;

  ; Get the vector information

  ;

  envi_evf_info, evf_id, num_recs=num_recs, $

     data_type=data_type, projection=projection, $

     layer_name=layer_name

  ;

  ; Print information about each record

  ;

  print, 'Number of Records: ',num_recs

  for i=0,num_recs-1 do begin  

     record = envi_evf_read_record(evf_id, i)  

     print, 'Number of nodes in Record ' + $         

        strtrim(i+1,2) + ': ', n_elements(record[0,*])

  endfor

  ;

  ; Close the EVF file

  ;envi_evf_close, evf_id

END