get rid of RuntimeWarning

[korpop]

/opt/conda/lib/python3.7/site-packages/numpy/lib/function_base.py:380: RuntimeWarning: Mean of empty slice.
avg = a.mean(axis)
/opt/conda/lib/python3.7/site-packages/numpy/core/_methods.py:163: RuntimeWarning: invalid value encountered in true_divide
ret, rcount, out=ret, casting='unsafe', subok=False)
/home/ext_choi_jinhwan_mayo_edu/bucket_data/lab_members/jinhwan/wsitiler/wsitiler/normalizer/MacenkoNormalizer.py:90: RuntimeWarning: Degrees of freedom <= 0 for slice
eigvals, eigvecs = np.linalg.eigh(np.cov(ODhat.T))
/opt/conda/lib/python3.7/site-packages/numpy/lib/function_base.py:2480: RuntimeWarning: divide by zero encountered in true_divide
c *= np.true_divide(1, fact)
/opt/conda/lib/python3.7/site-packages/numpy/lib/function_base.py:2480: RuntimeWarning: invalid value encountered in multiply
c *= np.true_divide(1, fact)
/home/ext_choi_jinhwan_mayo_edu/bucket_data/lab_members/jinhwan/wsitiler/wsitiler/normalizer/MacenkoNormalizer.py:117: RuntimeWarning: overflow encountered in exp
Inorm = np.multiply(Io, np.exp(-self.HERef.dot(C2)))
/home/ext_choi_jinhwan_mayo_edu/bucket_data/lab_members/jinhwan/wsitiler/wsitiler/normalizer/MacenkoNormalizer.py:122: RuntimeWarning: overflow encountered in exp
H = np.multiply(Io, np.exp(np.expand_dims(-self.HERef[:, 0], axis=1).dot(np.expand_dims(C2[0, :], axis=0))))
/home/ext_choi_jinhwan_mayo_edu/bucket_data/lab_members/jinhwan/wsitiler/wsitiler/normalizer/MacenkoNormalizer.py:122: RuntimeWarning: overflow encountered in multiply
H = np.multiply(Io, np.exp(np.expand_dims(-self.HERef[:, 0], axis=1).dot(np.expand_dims(C2[0, :], axis=0))))
/home/ext_choi_jinhwan_mayo_edu/bucket_data/lab_members/jinhwan/wsitiler/wsitiler/normalizer/MacenkoNormalizer.py:117: RuntimeWarning: overflow encountered in exp
Inorm = np.multiply(Io, np.exp(-self.HERef.dot(C2)))
/home/ext_choi_jinhwan_mayo_edu/bucket_data/lab_members/jinhwan/wsitiler/wsitiler/normalizer/MacenkoNormalizer.py:126: RuntimeWarning: overflow encountered in exp
E = np.multiply(Io, np.exp(np.expand_dims(-self.HERef[:, 1], axis=1).dot(np.expand_dims(C2[1, :], axis=0))))