Colormap in topoplot

[jgcordoba]

Hi to everyone!

When I try to create a colormap or make a discrete colormap from an existing one from matplotlib and apply it to the topoplot function, I get an error. I would like to know if this is possible or if there is not this functionality of using a different colormap than the original ones from matplotlib.

This is my script:

import numpy as np
from visbrain.objects import TopoObj, ColorbarObj, SceneObj
import matplotlib as plt

def discrete_cmap(N, base_cmap=None):
"""Create an N-bin discrete colormap from the specified input map"""

# Note that if base_cmap is a string or None, you can simply do
#    return plt.cm.get_cmap(base_cmap, N)
# The following works for string, None, or a colormap instance:

base = plt.cm.get_cmap(base_cmap)
color_list = base(np.linspace(0, 1, N))
cmap_name = base.name
return base.from_list(cmap_name, color_list, N)

m_data = np.array([210.55324061, 286.12320408, 158.11973237, 185.29573764,
193.14262184, 187.81332827, 218.20972376, 224.45368389])

kw_top = dict(margin=30 / 100, chan_offset=(0.1, 0.1, 0.), chan_size=10, cmap=discrete_cmap(5,'summer'))
kw_cbar = dict(cbtxtsz=12, txtsz=10., width=.3, txtcolor='black', cbtxtsh=1.8,
rect=(0., -2., 1., 4.), border=True)
kw_title = dict(title_color='black', title_size=11.0, width_max=300)

sc = SceneObj(bgcolor='white' )

ch_names = ['Fp1', 'Fp2', 'T3', 'T4', 'C3', 'C4', 'O1', 'O2']

Create the topoplot and the associated colorbar

t_obj = TopoObj('topo', m_data, channels=ch_names, **kw_top)
cb_obj1 = ColorbarObj(t_obj, cblabel='Colorbar label', **kw_cbar)
sc.add_to_subplot(cb_obj1, row=0, col=1, row_span=1, width_max=50)
sc.add_to_subplot(t_obj, row=0, col=0, title='Example', **kw_title)
sc.preview()

[EtienneCmb]

Hi @jgcordoba,

I'm don't think it is currently possible to create a discret colormap, but you can probably use an existing one (like set, set2 etc.)

Best,