matlab xget

[startz]

If you try to xget a structure from Matlab, EViews brings in a scalar with the wrong value. It should probably error.

If you type

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xget(type=structure) a

the error alert is too small and the title bar is truncated.

[EViews Steve]

Actually, the type=structure is invalid but our error message wasn't displaying properly. I've fixed this in the next patch.

[donihue]

Is there then any way to "xget" a Matlab structure?
Regards
Donihue

[EViews Gareth]

I believe not.

[EViews Glenn]

I would assume (but haven't verified) that you should be able to pull the individual elements of the structure as desired...

[donihue]

Perhaps one can, but I have failed... See the attached for one attempt. I also tried various other xget "type=" options, and none at all, with the same result. There may be some other appelation for "M_.params" which works, but "m_.params", "M_params" and "params" do not. And of course using "xget M_" directly just returns a scalar with value "NA".
Regards
Donihue

[EViews Steve]

I'm pretty sure that if you put M_.params into it's own separate matrix (within MATLAB) first, you can then download that new matrix variable to EViews with an XGET call.

This limitation is due to their own COM interface so it would be something they would have to change in order to allow a call to GetWorkspaceData M_.params (which is what the EViews XGET method calls) to work directly.

Another idea is that there are some MATLAB conversion functions they provide (such as cell2mat) that converts one type into another. Perhaps there is one for converting M_.params into a matrix. So maybe you could call something like

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XGET "cell2mat(M_.params)"

To figure out what class type M_.params is, try this MATLAB command:

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class(M_.params)

This could help figure out why it won't download directly...

Steve

[donihue]

Many thanks for your time, Steve.

The class of M_.params is the same as that of, say, the scalar sigas referenced in my output (namely, "double"), but the command "cell2mat(M_.params)" in Matlab just returns an error:
??? Cell contents reference from a non-cell array object.
Error in ==> cell2mat at 44
cellclass = class(c{1});

This is clearly a Matlab, not an EViews, issue, so I will try to figure out how to "put M_.params into it's own separate matrix (within MATLAB) first" as you suggest ...

Regards
Donihue

[EViews Steve]

Yeah, the cell2mat was just an example of a function you could use -- and it would only work if the M_.params object was a cell array.

What does class(M_.params) return?

[EViews Steve]

Nevermind my last question. I was able to replicate the issue...

[EViews Steve]

It looks like the MATLAB COM interface won't let you use compound statements in the call to GetWorkspaceData. Meaning, you can't call "func(M_.params)" to get your data. And from what I can see, there's no reason why you couldn't just call XGET M_.params aside from this limitation.

So here's what you should do:

Create a temp variable in MATLAB that copies the compound item you want to retrieve like this:

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XRUN "tmp2=M_.params"

Then retrieve it using the name parameter to change the name in EViews:

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XGET(type=vector, name=params) tmp2

Steve

[donihue]

Thank you very much indeed, Steve. That worked a treat!
Regards
Donihue