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Simple Scalar Quantities
The type descriptor for ``simple'' scalar quantities has the following
format. Here ``simple'' means integers, floating point values (real
and complex), strings, and pointers.
Format:
TYPEDESC_SCALAR (type descriptor for simple scalars)
Type
Name
Description
LONG
TYPECODE
IDL variable type code
LONG
VARFLAGS
Bit flags for a type descriptor, OR'd as follows:
'02'x
System variable
'04'x
Array (UNSET for scalar)
'10'x
Unknown?
'20'x
Structure (UNSET for scalar)
NOTES: All of the type descriptor formats begin physically with a
TYPECODE and VARFLAGS field. In the case of scalars, those are the
only two fields in the descriptor. All scalars have a VARFLAGS value
of zero or one, indicating either a system variable or not, but not an array or structure.
The IDL TYPECODE is the data type that is used throughout IDL, and by
the SIZE function, to describe the basic type of a quantity. The
values are contained in the following table:
0
Undefined (not allowed)
1
Byte
2
16-bit Integer
3
32-bit Long Integer
4
32-bit Floating Point Number
5
64-bit Floating Point Number
6
Complex Floating Point Number (32-bits each)
7
String
8
Structure (never a scalar)
9
Complex Floating Point Number (64-bits each)
10
Heap Pointer
11
Object Reference (not supported by CMSVLIB)
12
16-bit Unsigned Integer
13
32-bit Unsigned Integer
14
64-bit Integer
15
64-bit Unsigned Integer
The next sections describe the enhancements that are in place for
arrays and structures.
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Next: Arrays
Up: Data Type Descriptor Formats
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Craig Markwardt
2011年12月21日