mne.viz.plot_topomap

mne.viz.plot_topomap(data, pos, vmin=None, vmax=None, cmap='RdBu_r', sensors=True, res=64, axis=None, names=None, show_names=False, mask=None, mask_params=None, outlines='head', image_mask=None, contours=6, image_interp='bilinear', show=True, head_pos=None, onselect=None)

Plot a topographic map as image

Parameters:

data : array, length = n_points

The data values to plot.

pos : array, shape = (n_points, 2)

For each data point, the x and y coordinates.

vmin : float | callable | None

The value specifying the lower bound of the color range. If None, and vmax is None, -vmax is used. Else np.min(data). If callable, the output equals vmin(data). Defaults to None.

vmax : float | callable | None

The value specifying the upper bound of the color range. If None, the maximum absolute value is used. If callable, the output equals vmax(data). Defaults to None.

cmap : matplotlib colormap

Colormap.

sensors : bool | str

Add markers for sensor locations to the plot. Accepts matplotlib plot format string (e.g., ‘r+’ for red plusses). If True, a circle will be used (via .add_artist). Defaults to True.

res : int

The resolution of the topomap image (n pixels along each side).

axis : instance of Axis | None

The axis to plot to. If None, the current axis will be used.

names : list | None

List of channel names. If None, channel names are not plotted.

show_names : bool | callable

If True, show channel names on top of the map. If a callable is passed, channel names will be formatted using the callable; e.g., to delete the prefix ‘MEG ‘ from all channel names, pass the function lambda x: x.replace(‘MEG ‘, ‘’). If mask is not None, only significant sensors will be shown. If True, a list of names must be provided (see names keyword).

mask : ndarray of bool, shape (n_channels, n_times) | None

The channels to be marked as significant at a given time point. Indices set to True will be considered. Defaults to None.

mask_params : dict | None

Additional plotting parameters for plotting significant sensors. Default (None) equals:

dict(marker='o', markerfacecolor='w', markeredgecolor='k',
     linewidth=0, markersize=4)

outlines : ‘head’ | ‘skirt’ | dict | None

The outlines to be drawn. If ‘head’, the default head scheme will be drawn. If ‘skirt’ the head scheme will be drawn, but sensors are allowed to be plotted outside of the head circle. If dict, each key refers to a tuple of x and y positions, the values in ‘mask_pos’ will serve as image mask, and the ‘autoshrink’ (bool) field will trigger automated shrinking of the positions due to points outside the outline. Alternatively, a matplotlib patch object can be passed for advanced masking options, either directly or as a function that returns patches (required for multi-axis plots). If None, nothing will be drawn. Defaults to ‘head’.

image_mask : ndarray of bool, shape (res, res) | None

The image mask to cover the interpolated surface. If None, it will be computed from the outline.

contours : int | False | None

The number of contour lines to draw. If 0, no contours will be drawn.

image_interp : str

The image interpolation to be used. All matplotlib options are accepted.

show : bool

Show figure if True.

head_pos : dict | None

If None (default), the sensors are positioned such that they span the head circle. If dict, can have entries ‘center’ (tuple) and ‘scale’ (tuple) for what the center and scale of the head should be relative to the electrode locations.

onselect : callable | None

Handle for a function that is called when the user selects a set of channels by rectangle selection (matplotlib RectangleSelector). If None interactive selection is disabled. Defaults to None.

Returns:

im : matplotlib.image.AxesImage

The interpolated data.

cn : matplotlib.contour.ContourSet

The fieldlines.