Inverse wavelet synchrosqueezed transform

inverts
the input synchrosqueezed transform, `xrec`

= iwsst(`sst`

)`sst`

, and
returns the inverse in vector `xrec`

. To obtain
the `sst`

input, use the `wsst`

function.
The `iwsst`

function assumes that you obtain `sst`

using
the analytic Morlet wavelet.

**Note**

The wavelet transform does not preserve a nonzero mean. After inverting the synchrosqueezed transform, you must add back the original signal mean.

[1] Daubechies, I., J. Lu, and H. T. Wu. "Synchrosqueezed Wavelet Transforms: an Empirical
Mode Decomposition-like Tool." *Applied and Computational Harmonic
Analysis*, Vol. 30, Number 2, 2011, pp. 243–261.

[2] Thakur, G., E. Brevdo, N. S. Fučkar, and H. T. Wu. "The Synchrosqueezing algorithm for
time-varying spectral analysis: robustness properties and new paleoclimate
applications." *Signal Processing*, Vol. 93, Number 5, 2013, pp.
1079–1094.