def fit(self, imgs=None, y=None):
super().fit(imgs, y)
if self.reduction is not None:
if self.reduction == 'labels':
self.maps_img_ = self.memory.cache(label_to_maps)(
self.label_img)
else:
self.maps_img_ = self.maps_img
simple_masker = NiftiMasker(mask_img=self.mask_img_).fit()
self._masked_maps_ = simple_masker.transform_single_imgs(
self.maps_img_)
self._masked_maps_inv_ = np.linalg.pinv(self._masked_maps_)
return self
