The CDF_ATTGET_ENTRY procedure reads a variable attribute entry from a CDF file.
CDF_ATTGET_ENTRY, Id, Attribute, EntryNum, AttributeEntryType, Value, Status [, CDF_TYPE=variable] [, ATTRIBUTE_NAME=string] [, /ZVARIABLE ]
The CDF ID, returned from a previous call to CDF_OPEN or CDF_CREATE.
A string containing the name of the attribute or the attribute number to be written.
The entry number. If the attribute is variable in scope, this is either the name or number of the variable the attribute is to be associated with. If the attribute is global in scope, this is the actual gEntry. It is the user's responsibility to keep track of valid gEntry numbers. Normally, gEntry numbers begin with 0 or 1 and increase to MAXGENTRY (as reported in the GET_ATTR_INFO structure returned by CDF_CONTROL), but this is not required.
The data type of the requested attribute entry.
A named variable that will contain the attribute value.
The procedure return status. A value of 1 is returned if the requested attribute exists and its entry is retrieved. Otherwise, 0 is returned.
Set this keyword to a named variable that will contain the CDF type of the attribute entry, returned as a scalar string. The possible string values are:
CDF_CHAR
CDF_UCHAR
CDF_INT1
CDF_BYTE
CDF_UINT1
CDF_UINT2
CDF_INT2
CDF_UINT4
CDF_INT4
CDF_REAL4
CDF_FLOAT
CDF_REAL8
CDF_DOUBLE
CDF_EPOCH
CDF_EPOCH16
If the type cannot be determined, “UNKNOWN” is returned.
Set this keyword to a named variable that will hold the name of the requested attribute number.
If EntryNum is a variable ID (as opposed to a variable name) and the variable is a zVariable, set this flag to indicate that the variable ID is a zVariable ID. The default behavior is to assume that EntryNum is an rVariable ID.
Note: The attribute must have a scope of VARIABLE_SCOPE.
id = CDF_OPEN('test.cdf')
inq = CDF_INQUIRE(id)
; Read all the variable attribute entries.
; Walk through all of the zVariables
FOR varNum = 0, inq.nzvars-1 DO BEGIN
; Walk through all of the ZVariable attributes
FOR attrNum = 0, inq.natts-1 DO BEGIN
; Read the variable attribute
CDF_ATTGET_ENTRY, id, attrNum, varNum, attType, value, $
status, /ZVARIABLE, CDF_TYPE=cdfType, $
ATTRIBUTE_NAME=attName
IF STATUS NE 1 THEN CONTINUE
PRINT, "attr_name = ", attName, ", ", cdfType, ", ", $
value
ENDFOR
ENDFOR
|
8.0 |
Introduced |