Convert MATLAB Types to COM Types

Data types for the arguments and return values of the server functions are expressed as Automation data types, which are language-independent types defined by the Automation protocol. For example, BSTR is a wide-character string type defined as an Automation type, and is the same data format used by the Visual Basic^® language to store strings. Any COM-compliant client should support these data types, although the details of how you declare and manipulate these types are client specific.

This table shows how MATLAB^® converts data from MATLAB to COM types.

MATLAB Type	Closest COM Type	Allowed Types
handle	`VT_DISPATCH` `VT_UNKNOWN`	`VT_DISPATCH` `VT_UNKNOWN`
character vector	`VT_BSTR`	`VT_LPWSTR` `VT_LPSTR` `VT_BSTR` `VT_FILETIME` `VT_ERROR` `VT_DECIMAL` `VT_CLSID` `VT_DATE`
`int16`	`VT_I2`	`VT_I2`
`uint16`	`VT_UI2`	`VT_UI2`
`int32`	`VT_I4`	`VT_I4` `VT_INT`
`uint32`	`VT_UI4`	`VT_UI4` `VT_UINT`
`int64`	`VT_I8`	`VT_I8`
`uint64`	`VT_UI8`	`VT_UI8`
`single`	`VT_R4`	`VT_R4`
`double`	`VT_R8`	`VT_R8` `VT_CY`
`logical`	`VT_BOOL`	`VT_BOOL`
char	`VT_I1`	`VT_I1` `VT_UI1`

Variant Data

variant is any data type except a structure or a sparse array. (For more information, see Fundamental MATLAB Classes.)

When used as an input argument, MATLAB treats variant and variant(pointer) the same way.

If you pass an empty array ([]) of type double, MATLAB creates a variant(pointer) set to VT_EMPTY. Passing an empty array of any other numeric type is not supported.

MATLAB Argument	Closest COM Type	Allowed Types
`variant`	`VT_VARIANT`	`VT_VARIANT` `VT_USERDEFINED` `VT_ARRAY`
`variant(pointer)`	`VT_VARIANT`	`VT_VARIANT` \| `VT_BYREF`

SAFEARRAY Data

When a COM method identifies a SAFEARRAY or SAFEARRAY(pointer), the MATLAB equivalent is a matrix.

MATLAB Argument	Closest COM Type	Allowed Types
`SAFEARRAY`	`VT_SAFEARRAY`	`VT_SAFEARRAY`
`SAFEARRAY`(pointer)	`VT_SAFEARRAY`	`VT_SAFEARRAY` \| `VT_BYREF`

VT_DATE Data Type

To pass a VT_DATE type input to a Visual Basic program, use the MATLAB class COM.date. For example:

d = COM.date(2005,12,21,15,30,05);
get(d)
     Value: 7.3267e+005
    String: '12/21/2005 3:30:05 PM'

Use the now function to set the Value property to a date number:

d.Value = now;

COM.date accepts the same input arguments as datenum.

Unsupported Types

MATLAB does not support these COM types.

String array
Structure
Sparse array
Multidimensional SAFEARRAYs (greater than two dimensions)
Write-only properties