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We assume that a file dc.page exits and contains plots of dispersion curves , slowness versus frequency. We want to transform them into wavelength versus slowness. Additionally, we would like to smooth these curves in a "clever" way which keep the up-down traveltimes constant.

We first extract the content.xml file contained in the .page file: The content.xml file is an xml file encoded in UTF16 (unicode). With 'cat', 'awk',... unicode may not be considered properly. First we convert it to basic ascii encoding: All dispersion curves can be extracted from the xml content: The next step is to modify these parts of the xml content without touching the rest. We replace the [frequency,slowness] by [slowness, 1/(frequency*slowness)=wavelength]. We re-direct everything to content.xml to build a new .page file. If the original dc.page contains other files (usually starting by bin_...) you must pack them as well in the new file. Skip 'bin_data_100*' if your original dc.page file contains no binary file. The created file can opened in figue: You may be a bit disappointed because all plots are probably blank. This is just a problem of axis limits. Change the axis properties as you want, make use of mkup files to propagate them if you have various plots. Save your changes to dc-wavelength.page.

Secondly, we can calculate the smoothed slowness curves keeping the traveltimes constant. We start from the last dc-wavelength.page.
We first extract the content.xml file contained in the .page file and convert it: We revert the sort of curves obtained so far to get increasing wavelengths: We compute the smoothing itself: The contents.xml can be converted to .page file the same way as shown above.

Hi Marc,

I just tried to follow your instructions about converting the dispersion curves from the page file (for our brandnew NERIES data), but when I type the third line

cat contents-ascii.xml | awk '/[0-9\.]+ +[0-9\.]+ +[0-9\.]+/{print $2 " " 1/($1*$2)}!/[0-9\.]+ +[0-9\.]+ +[0-9\.]+/{print $0}' > contents.xml

my computer responds:

/[0: Event not found.

As I'm not so familiar with regular expressions (at least not with such complicated ones), I do not know what it does not like about the !/ stuff... Any idea? Should this work for all shells or just in bash? (Already tried both bash and csh, no difference in response).

Brigitte

Just found out what was the difficulty - in my bash, I need to add a space behind the "!" so the regular expression is interpreted correctly.

Brigitte