IeegReference

Namespace: IEEGLIB  ·  Library: iEEG Library

Python equivalent

mne.set_bipolar_reference in MNE-Python.

#include <ieeg/ieeg_reference.h>

class IEEGLIB::IeegReference

Bipolar montages along sEEG / ECoG leads.

src/examples/ex_ieeg/main.cpp

const QVector<IeegBipolarPair> pairs = IeegReference::bipolarPairs(implantation); // LA1-LA2, LA2-LA3
Eigen::MatrixXd data(3, 1);                                                       // contacts x samples, file order
data << 30.0, 10.0, 15.0;                                                         // LA3, LA1, LA2
const Eigen::MatrixXd bipolar = IeegReference::bipolarMatrix(pairs, int(contacts.size())) * data;

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Static Methods

bipolarPairs(implantation)

Pair each contact with its next neighbour on the same lead: along a depth lead or strip, and along the rows and then the columns of a grid with a known shape.

The contact earlier along the lead is the anode, so a depth lead gives LA1-LA2, LA2-LA3, …

Parameters:

• implantation : const IeegImplantation & Contacts and leads.

Returns:

• QVector< IeegBipolarPair > — The derivations, lead by lead.

---

bipolarMatrix(pairs, contactCount)

Montage matrix of the derivations: bipolar data = M * contact data.

Parameters:

• pairs : const QVector< IeegBipolarPair > & Derivations.

• contactCount : int Number of contacts, the columns of M.

Returns:

• Eigen::SparseMatrix< double > — Sparse pairs x contacts matrix, +1 at the anode and -1 at the cathode of each row.

---

Example

• Full source: src/examples/ex_ieeg/main.cpp
• Build target: ex_ieeg (runs under CTest)

Used in examples

ex_ieeg

IEEG library: group sEEG contacts into a lead, derive a bipolar montage and paint contact values onto a surface.

src/examples/ex_ieeg/main.cpp, line 80

const QVector<IeegBipolarPair> pairs = IeegReference::bipolarPairs(implantation); // LA1-LA2, LA2-LA3
Eigen::MatrixXd data(3, 1);                                                       // contacts x samples, file order
data << 30.0, 10.0, 15.0;                                                         // LA3, LA1, LA2
const Eigen::MatrixXd bipolar = IeegReference::bipolarMatrix(pairs, int(contacts.size())) * data;
ok &= expect(pairs.size() == 2 && pairs[0].name == "LA1-LA2" && bipolar(0, 0) == -5.0 && bipolar(1, 0) == -15.0,
             "IeegReference: LA1-LA2 = -5, LA2-LA3 = -15");

Authors of this file

• Christoph Dinh <christoph.dinh@mne-cpp.org>