I have irregularly sampled data that looks as in the picture.
Is there a function in Mathematica that allows me to find an approximate or average period or wavelength?
I know beforehand that the data will always look like this, with some random wiggling.
If there is no function that does this, how best to do it in Mathematica?
This is a link to the data. The data is very sparse at the beginning and grows denser towards the end. Use
ListLinePlot rather than
ListPlot to visualize:
EDIT It is hard to choose a best solution. Perhaps D. Lichtbau's solution using the irregular periodogram function in the function repository I like the most, but I also very much like the fitting solution, as it returns all the parameters needed to make a visual check of the hypothesized periodicity of the data. And as remarked by Roman in a comment, perhaps the best is to use these two in combination. For the sake of just choosing one, I will choose Daniel Lichtbau's solution, perhaps because it is the closest thing to having a function within the Wolfram Language that does what we want.