Power Law
y proportional to a power of x. Use it for scaling laws, such as a pendulum’s period against its length or radiated power against temperature.
Fit the example dataStart with your own data
Example: NIST’s DanWood carbon filament radiation data, 6 points with y uncertainties, opened as a new copy you can edit.
Parameters
- Value of y at x = 1.
- Exponent.
Tips
- Use x ≥ 0 unless B is a whole number: a non-integer power of a negative number is not real. A point at x = 0 needs a positive B.
- Automatic starting values try a range of exponents and solve A exactly, so negative y needs no guesses.
- On logarithmic x and y axes a power law is a straight line with slope B.