The data can have the form , where the number of coordinates is equal to the number of variables in the list vars.
The data can also be of the form , with a single coordinate assumed to take values 1, 2, ....
The argument funs can be any list of functions that depend only on the objects vars.
Fit[{f1, f2, ...}, {1, x, x^2}, x] gives a quadratic fit to a sequence of values fi. The result is of the form a0+a1x+a2x^2, where the ai are real numbers. The successive values of x needed to obtain the fi are assumed to be 1, 2, ... . »
Fit[{{x1, f1}, {x2, f2}, ...}, {1, x, x^2}, x] does a quadratic fit, assuming a sequence of x values xi. »
Fit[{{x1, y1, f1}, ...}, {1, x, y}, {x, y}] finds a fit of the form a0+a1x+a2y. »
Fit always finds the linear combination of the functions in the list funs that minimizes the sum of the squares of deviations from the values fi. »
Exact numbers given as input to Fit are converted to approximate numbers with machine precision. »