---

Authors:

• Benjamin Audit
  EMBL Outstation - Hinxton, European Bioinformatics Institute,
  Wellcome Trust Genome Campus, Hinxton,
  Cambridge, CB10 1SD,
  United Kingdom

• Emmanuel Bacry
  Centre de Mathematiques Appliquées
  Ecole Polytechnique 91128 Palaiseau Cedex - France

• Jean François Muzy
  Université de Corse, Quartier Grossetti,
  20250, Corté, France.

• Cédric Vaillant
  Formerly at Centre de Recherche Paul Pascal
  33600 Pessac - France

Description

Package allowing to deal with 1d wavelet transform local extrema

Examples

Let's run the Demo DemoExtrema1dSing

Let's run the Demo DemoExtrema1dSing
Here is the code of the demo:
# Set the current wavelet transform to be a
a
# Generate the signal (a singularity of Holder .5)
0 = [_DemoSing 10000 .5]
# Adds noise to it
0= 0a+.02*Grand
# Compute the wavelet transform
cwtd 3 6 8 'g1'
# Compute the extrema representation
extrema
# Display the signal, the wavelet transform and the extrema representation
disp 0 a a.extrep

If you zoom one of the graph (using the mouse or the command line) everything is zoomed:

Then you can select a maxima line and draw the log(values) of the wavelet transform along this line (using sift+left mouse button). Then you can perform a linear fit in order to obtain an estimation of the Holder exponent