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isfilevaratt

Checks if specified file variable attributes are defined for a file variable.

Prototype

	function isfilevaratt (
		thefile [1] : file,    
		varname [1] : string,  
		attnames    : string   
	)

	return_val [dimsizes(attnames)] :  logical

Arguments

thefile

reference to a file. This must be created via addfile. This must be a supported file format.

varname

varname must be single string variable name.

attnames

attnames must be an array type string, but can have any dimension.

Return value

The output of isfilevaratt is a logical array with the same dimensions as the attnames parameter. If the parameter thefile is not a valid file or varname isn't a defined file variable, then a single missing value is returned.

Description

For each element in the attnames parameter, isfilevaratt returns True if the element is an attribute of the file variable varname in the file thefile and False if not.

See Also

isatt

Examples

Example 1 Before reading a variable ("TEMP") to memory, check to see if it has specific attributes. 

    f = addfile ("foo.nc", "r")

    attNames = (/"long_name", "description", "units", "scale_factor"/)
    tf       = isfilevaratt(f, "TEMP", attNames)    ; ==> tf(4)
   
    print(tf)   ; each element will be True or False