非公式広島大学病院脳磁図室ホームページGraph篇

Kajola氏からの返事

Graphにはもっといろいろな機能があるはずなのですが、詳細はKajola氏しかわかりません。以下はKajola氏に質問した返事です。ニューロマグ・ユーザーの共通の知識としてエレクタが各サイトに通知できる態勢が整うまで、このホームページ上で公開します。

一応 Matti Kajola氏本人からは2003年7月25日に

Can I open how to use Graph in our Home Page?

Yes you can.
I think that would help me too by making the number of questions smaller.

Iloisin terveisin,
Matti K.

との返事を得ています。

magnetometer、gradiometerだけにPCAをかける方法

xfitにSSP情報を付加する方法

Graph加算波形にポルヘムスの点情報を加える方法

magnetometer、gradiometerだけにPCAをかける方法

Can Graph make projection vectors which consist of 204 gradiometer component and 102 magnetometer component separately?
I want to distinguish gradiometer-ssp from magnetometer-ssp.

Easily, this is actually the normal way. Simply select only gras or mags to the "meg" widget when you calculate the vectors.

However, I thnk these projection vectors consist of not 1x306 but 1x204 or 1x102 matrix.

Aha.. This is bit more complicated but can be done:

1) Select the wanted channels, e.g. magnetometers and calculate PCA -> SSP vectors (these are e.g. n * 102). e.g. my_ssp.fif
2) With the same settings, save a short piece of data, e.g. sample.fif.
3) Run /neuro/bin/util/add_proj_namelist -f sample.fif my_ssp.fif
4) Open some 306 ch file in xfit.
5) Load projections from my_ssp.fif.
6) Save the projections.
The result should be n * 306 vectors.

xfitにSSP情報を付加する方法

In Graph, 'xfit' can transfer selected MEG data to Source Modelling, but SSP information is not transfered even SSP widget exists. Is there any solution or Is there Graph commands which can regulate linear projection in Source Modelling?

The SSP vector info does not currently "flow" through widgets like channel positions, calibraions etc. Therefore it is a bit difficult to get the projections into the output data.

I once tried adding a call to an external program to copy the SSP vector info when saving averages. The problem there was that sometimes the SSP is needed, sometimes it should not be there (like with spectra).

I will include the code and the program. You can try how they work. You can change e.g. the name of the routine, so you can select if you want to copy the ssp info or not. The xfit module uses make-evoked-file to create the temporary file, so using this should add the ssp vetors into the xfit data too.

make-evoked-file-upgrade.lsp(3.07kB)

Graph加算波形にポルヘムスの点情報を加える方法

Can Graph add digitized points information to newly made evoked fiff file after (save-evoked-data ....)?

Currently there is only a utility to copy the transfomation matrix, as far as I remember that one is not copying the digitization points.

copy_proj_fiff(123kB)