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readAsciiHead

Reads an ASCII file and returns just the header.

Prototype

load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/contributed.ncl"  ; This library is automatically loaded
                                                             ; from NCL V6.2.0 onward.
                                                             ; No need for user to explicitly load.

	function readAsciiHead (
		filename  : string,  
		opt                  
	)

	return_val [*] :  string

Arguments

filename

The filename to read.

opt

If opt is an integer or long, then it is the number of rows (lines) for the header. This is a "fixed" number of lines.

If opt is a string, then it is a sequence of characters that terminate a variable number of header rows. Currently this just checks character sequences starting in column 0.

If opt is a float and positive, then it will read all values as float.

Return value

A one-dimensional array of strings. Each row in the header will be one string.

Description

This function reads an ASCII file and returns just the header as an array of strings. The header is the non-numeric part. Note upon return, the return values may have to be parsed individually for specific info.

Examples

Example 1

Assume you have the file:

   DARWIN SEA LEVEL PRESS (1000 MB SUBTRACTED)                                  
   YEAR   JAN   FEB   MAR   APR   MAY   JUN   JUL   AUG   SEP   OCT   NOV   DEC 
   1951   5.3   5.1   7.0   9.4  11.9  11.2  13.3  13.2  12.5  11.4   9.5   8.9 
   1952   6.7   7.1   8.3  10.3  10.3  12.5  13.0  12.6  12.1   9.9   7.7   8.4 
   [snip]

Then the following script:

   head = readAsciiHead("darwin", 2)     ; there are two header lines
   print(head)

   head = readAsciiHead("darwin", "YEAR"); the line that begins with year
                                         ; is the last header line
   print(head)

will produce: