| Description: | The correlomatrix_detector is a recording device. It is used to record spikes from
several pools of spike inputs and calculates the covariance matrix of inter-spike intervals
(raw auto and cross correlation) binned to bins of duration delta_tau. The histogram is only
recorded for non-negative time lags. The negative part can be obtained by the symmetry of the
covariance matrix C(t) = C^T(-t).
The result can be obtained via GetStatus under the key /count_covariance.
In parallel it records a weighted histogram, where the connection weight are used to weight every
count, which is available under the key /covariance.
Both are matrices of size N_channels x N_channels, with each entry C_ij being a vector of
size tau_max/delta_tau + 1 containing the (weighted) histogram for non-negative time lags.
The bins are centered around the time difference they represent, and are left-closed
and right-open in the lower triangular part of the matrix. On the diagonal and in the upper
triangular part the intervals are left-open and right-closed. This ensures proper counting
of events at the border of bins, allowing consistent integration of a histogram over negative
and positive time lags by stacking two parts of the histogram (C(t)=[C[i][j][::-1],C[j][i][1:]]).
In this case one needs to exclude C[j][i][0] to avoid counting the zero-lag bin twice.
The correlomatrix_detector has a variable number of inputs which can be set via SetStatus under
the key N_channels. All incoming connections to a specified receptor will be pooled.
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| Parameters: |
Tstart double - Time when to start counting events. This time should be set to at least
start + tau_max in order to avoid edge effects of the correlation counts.
Tstop double - Time when to stop counting events. This time should be set to at most
Tsim - tau_max, where Tsim is the duration of simulation,
in order to avoid edge effects of the correlation counts.
delta_tau double - bin width in ms. This has to be an odd multiple of the resolution, to allow
the symmetry between positive and negative time-lags.
tau_max double - one-sided width in ms. In the lower triagnular part events with differences in
[0, tau_max+delta_tau/2) are counted. On the diagonal and in
the upper triangular part events with differences in (0, tau_max+delta_tau/2]
N_channels long - The number of pools. This defines the range of receptor_type. Default is 1.
Setting N_channels clears count_covariance, covariance and n_events.
covariance matrix of double vectors, read-only - raw, weighted auto/cross correlation counts
count_covariance matrix of long vectors, read-only - raw, auto/cross correlation counts
n_events integer vector - number of events from all sources.
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