# Binning¶

Binning (or *bunching*) consists in grouping the terms of a statistical series in order to reduce its autocorrelation time. If the bin size is large enough, the samples of the binned series are uncorrelated; as a result, its error bar can be computed easily, i.e

\[\Delta \langle X \rangle = \sqrt{\frac{\tilde{\sigma}^2} {\tilde{N}-1}}\]

where \(\tilde{\sigma}^2\) and \(\tilde{N}\) are respectively the variance and size of the binned series.

## Synopsis¶

- make_binned_series(T series, int bin_size)
- series: object with
**TimeSeries**concept - bin_size: size of the bin

returns the binned time series.

- series: object with

## Example¶

```
#include <triqs/statistics.hpp>
using namespace triqs::statistics;
int main() {
observable<double> A;
A << 1.;
A << 1.5;
A << .2;
A << 1.1;
auto A_b = make_binned_series(A, 2);
std::cout << A_b << std::endl;
return 0;
}
```