`unfold` converts the two-dimensional chromatograms into a one dimensional vector. Then, all chromatograms are joined into a matrix.

## Details

This function takes a single argument, batch_2DCOW or joined_chrom objects and extracts each chromatogram and then it is unfolded into a one-dimensional vector. Then, each one dimensional vector is joined in a single matrix, where each row represent an observation or a chromatogram and each column represent a variable, in our case, each retention time. Also, in order to keep information about chromatographic runs, the retention times for both dimensions are also exported.

## Examples

```
data(Myrothecium)
# Unfold 2D chromatogram
chrom_1D <- unfold_chrom(Myrothecium)
# Retrieve retention time for the first dimension
time_1D <- chrom_1D$time
# Retrieve the modulation time
modulation <- chrom_1D$mod_time
```