Sigfit 1.2

Optimize math calculations for different purposes and projects managed on your Mac. Work with such materials as Alkaline sigmoid kobs = k/(1+[H]/Ka), Acid sigmoid kobs = k/(1+Ka/[H], etc. Automatically make initial estimates of kobs and the pKa for further calculations.

This program fits data to the equations:-

Alkaline sigmoid

kobs = k/(1+[H]/Ka)

Acid sigmoid

kobs = k/(1+Ka/[H]

When "Fit" is selected a linear reciprocal plot is used to make the initial estimates of kobs and the pKa. These values of kobs and pKa are then used as the initial estimates to fit the experimental data using an iterative, non linear least-squares regression program.

When "Fit with estimates" is selected you must input the initial estimates of kobs and the pKa. The experimental data is then fitted using an iterative, non linear least-squares regression program.

Results can be printed, saved as a text document or copied and pasted into other applications such as Word.

Instructions and test data are provided.