FUNCTION: cdf_var_exists, cdf, varname PURPOSE: determines if a specified CDF file has a variable 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 variable to be asked about KEYWORDS: OUTPUTS: return value is 1 if yes, 0 if no CREATED BY: Vince Saba LAST MODIFICATION: @(#)cdf_var_exists.pro 1.1 98/04/14