FUNCTION: cdf_attr_exists, cdf, attrname PURPOSE: determines if a specified CDF file has an attribute with a specified name INPUTS: cdf: either the cdf_id of an open CDF file, or the name of a CDF file attrname: name of the attribute to be asked about KEYWORDS: scope: if set, return the scope of the attribute (if it is present). The scope may be either of the strings 'GLOBAL_SCOPE' or 'VARIABLE_SCOPE'. The value of this variable is only meaningful if the return value is 1. OUTPUTS: return value is 1 if yes, 0 if no CREATED BY: Vince Saba LAST MODIFICATION: @(#)cdf_attr_exists.pro 1.1 98/04/14