# pyblp.exceptions.DeltaNumericalError¶

class pyblp.exceptions.DeltaNumericalError

Encountered a numerical error when computing $$\delta$$.

This problem is often due to prior problems, overflow, or nonpositive shares, and can sometimes be mitigated by choosing smaller initial parameter values, setting more conservative bounds on parameters or shares, rescaling data, removing outliers, changing the floating point precision, or using different optimization, iteration, or integration configurations.