screenshot Welcome to the



(last update: 13/05/2013)

Downloads (9.0 MB)
Executable file and DLLs for 32-bit Windows. Simply extract the content of this archive and run LambdaFit_2.1.exe. (0.05 MB)
The source code of LambdaFit to modify or compile it yourself (both Windows and Linux).
(A readme.txt is included.) (0.1 MB)
Some example pictures to test the functionality of LambdaFit with.
(You can also test LambdaFit with the original pictures provided as supplementary publication data below.)

Supplementary data for the publication
"Assessment of shape changes of mistletoe berries:
A new software approach to automatize the parameterization of path curve shaped contours"

For “historical” reasons we are also providing the binaries and source code of the outdated first version LambdaFit 1.7: (7.5 MB) (0.02 MB)


LambdaFit is a software meant to assist biology researchers in a task of measuring the shapes of plant buds and berries in digital photographs.

Lawrence Edwards (1912-2004) discovered that such shapes are accurately described through so called path curves stemming from the mathematical field of projective geometry. He furthermore conducted extensive experimental research suggesting that these shapes are subject to rythmic changes over time. The path curve parameter corresponding to these changes is called Lambda.

To verify and continue the work started by Lawrence Edwards, researchers have to examine great amounts of plant photographs. For each photograph they have to find the Lambda value (i.e. path curve) which best fits the shape of the photographed bud or berry. LambdaFit assists the researcher by helping with the fitting of the path curve, saving the results, and blinding the photographs prior to the measuring.

On this webpage we want to make LambaFit available to the public by providing its C source code and a compiled version for 32-bit Windows.

  • For further information on Lawrence Edward's findings see for example:
    Lawrence Edwards, "The Vortex of Life: Nature's Patterns in Space and Time",
    Floris Books, 2nd edition (2006), ISBN: 978-0863155512


LambdaFit uses the follwing libraries:

To compile the Windows version, MinGW and MSYS were used.


If you have questions regarding LambdaFit or the research it is connected to, do not hesitate to contact us!

Linus Feiten (
Renatus Derbidge (