Parameter: ncarlo
Definition
How often to measure the physical observables.
Type
Integer
Default value
10
Component
All
Behavior
Every ncarlo Monte Carlo sampling steps, the quantum impurity solvers try to measure the physical observables. The affected physical observables are as follows:
- Atomic state probability, $P_{\Gamma}$,
- Imaginary-time Green's function, $G(\tau)$,
- Auxiliary imaginary-time correlation function, $F(\tau)$.
The measuring period for the other physical observables are controlled by the nmonte parameter. See also nmonte parameter for more details.
The histogram for the perturbation expansion series is measured in each Monte Carlo sampling step.
Comment
You can increase ncarlo to relieve the auto-correlation of physical observables > between two successive measurements. However, large ncarlo will waste the CPU times. What's the best choices? We guess a good ncarlo should satisfy the following relation:
\[\text{ncarlo} * \text{P}_{\text{insert}} >= 1.0\]
Here, $\text{P}_{\text{insert}}$ means the accepted ratio for the insert update actions.