def updateIntensities(self, fiContainer, iKey='intensity'):
        """ #TODO: docstring
        :param fiContainer:
        :param iKey: Attribute name of :class:`Fi` that contains the feature
            intensity or an abundance measure. Default "intensity"
        """
        for fgi in listvalues(self.container):
            intensities = list()
            specfileIds = {i: j for i, j in zip(fgi.specfiles, fgi.featureIds)}
            for specfile in self._matrixTemplate:
                if specfile in specfileIds:
                    fi = fiContainer.getItem(specfile, specfileIds[specfile])
                    intensities.append(getattr(fi, iKey))
                else:
                    intensities.append(None)
            fgi.intensities = intensities