np.any() to trigger emittance calculation with dispersion instead of np.all()

mbtrack2/tracking/particles.py

@@ -288,7 +288,7 @@ class Bunch:
         cov_z = np.cov(self['tau'], self['delta'])
 
         if (np.array(self.ring.optics.local_dispersion)
-                != np.array([0, 0, 0, 0])).all():
+                != np.array([0, 0, 0, 0])).any():
             cov_xdelta = np.cov(self['x'], self['delta'])
             cov_xpdelta = np.cov(self['xp'], self['delta'])
             cov_ydelta = np.cov(self['y'], self['delta'])