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fileexists

Checks for existence of any UNIX file.

Available in version 6.2.1 and later.

Prototype

	function fileexists (
		file_path  : string   
	)

	return_val [dimsizes(file_path)] :  logical

Arguments

file_path

A scalar string or a multi-dimensional array of strings containing the full or relative path to UNIX files (Unix pathname string) for which to check presence on the filesystem.

Return value

The output of fileexists is a logical variable with the same dimension sizes as the input.

Description

The function fileexists returns True for every element of file_path that is present, and False if not.

This function was created in NCL V6.2.1, to complement the isfilepresent function, which now only returns True if the file is present and it is a supported format recognized by addfile.

See Also

isfilepresent

Examples

Example 1

The following code will determine if an ASCII file named "StationData.csv" exists before trying to read it in:

  filename = "StationData.csv"
  if (fileexists(filename)) then
    lines = asciiread (filename,-1,"string")
  end if

Example 2

The following code will determine if each of a group of files called "StationData_1.txt", "StationData_2.txt", ..., "StationData_5.txt" exists:

  filenames = "StationData_" + ispan(1,5,1) + ".txt"
  if (all(fileexists(filename))) then
    . . .  do something here . . .
  end if