galpy.df.streamdf.freqEigvalRatio

streamdf.freqEigvalRatio(isotropic=False)

Calculate the ratio between the largest and 2nd-to-largest (in abs) eigenvalue of sqrt(dO/dJ^T V_J dO/dJ) (if this is big, a 1D stream will form)

Parameters:

isotropic (bool, optional) – If True, return the ratio assuming an isotropic action distribution (i.e., just of dO/dJ)

Returns:

Ratio between eigenvalues of fabs(dO / dJ)

Return type:

float

Notes

• 2013-12-05 - Written - Bovy (IAS)