Open a connection to an external application.
Syntax
xopen(options)
xopen is used to start a COM session with an external application, either R or MATLAB. EViews can only have a single session open at a time; a session must be closed (see
xclose) before a new session can be opened.
Options
type=arg | Set the type of connection to be opened. arg may be “r” (R) or “m” (MATLAB). |
keepcurrent | If “type=” is the same as a currently open connection, keep original connection since it is already open. |
progid=arg | (optional) Set the version of MATLAB or statconnDCOM to which EViews connects when opening a session. If not specified, EViews will use the default ProgID specified in the global options. |
nolog | Do not open a session log window. |
case=arg | Specify the default case for objects in R or MATLAB using
xput. If “case=” is not provided, the default case specified in the global options will be assumed. Note that once a connection has been opened, the case option cannot be changed; you may however, use the “name=” option when using
xput to provide an explicit name. |
Note that the MATLAB ProgIDs may be of particular interest as MATLAB (R2008a and later) offers several distinct ways in which to connect to the server. The relevant ProgIDs are:
1. “MATLAB.Application”— this ProgID starts a command window version of MATLAB that was most recently used as a server (might not be the latest installed version of MATLAB).
2. “MATLAB.Application.Single”— same as (1) but starts a dedicated server so that other programs looking to use MATLAB cannot connect to your instance.
3. “MATLAB.Autoserver”—starts a command window server using the most recent version of MATLAB.
4. “MATLAB.Autoserver.Single”—same as (3) but starts a dedicated server.
5. “MATLAB.Desktop.Application”—starts the full desktop MATLAB as a server using the most recent version of MATLAB.
Each ProgID may be amended to indicate a specific version of MATLAB. For example, using the ProgID:
MATLAB.Desktop.Application.7.6
instructs EViews to use the full desktop MATLAB GUI for version R2008a (v7.6) as the Automation server.
Examples
xopen(type=m)
opens a connection to MATLAB.
xopen(type=r, case=lower)
opens a connection to R and sets the default name-case to lower.
xopen(type=m, progid=MATLAB.Desktop.Application.7.9)
opens a connection to MATLAB 7.9 running with the full desktop GUI.
Cross-references