Calculation of upper and lower envelopes of a dataset (envelope)

envelope is a command line utility that calculates the upper and lower envelopes of a dataset.

The upper envelope is obtained by a cubic spline interpolation of the dataset maximas. Similarily, the lower envelope is obtained by a cubic spline interpolation of the dataset minimas.


$ envelope -i test.txt -o test_out.txt -vvv
Reading file test.txt ...
Read 2650 entries.
Aberrant Limit 1.80e+308.
Saving data to test_out.txt
The graph here below shows how a dataset (gray) is bounded by lower (green) and upper (red) envelopes.
Example of envelope calculations


envelope has been developped in C ANSI. It has been tested on Linux platforms (gcc) as well as on Windows (Visual Studio C++)

Current version is 1.0.0.
envelope binary and source can be downloaded through anonymous SVN at the following address:

Change Log


Under Windows, the binary runs directly without installation.
Under Linux, the classic installation steps are used: ./configure, make, make install. Please read the INSTALL file from the package for details.


] [-o ]
      [-a    .
    a	Threshold for aberrant values suppression. Difference between two
   		consecutive data must not exceed the specified value.
   		Aberrant values suppression is not enabled by default.
Creative Commons License SID monitoring station by Lionel LOUDET is licensed under a
Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License.
Contact the webmaster
Last Update: 10 Dec 2010 Visitors Today:
Apache Web Server PHP
Apache/2.4.25 (Debian)
Valid XHTML + RDFa Valid CSS!
Page generated in 0.306 seconds.