From ftp://ftp.mathworks.com/pub/contrib/v4/stats/chisquared/Chi-squared probability function.Abstract m-files to compute the Chi-squared probability function, andthe percentage points of the probability function.P = CHISQUARED_PROB( X2, v ) returns P(X2|v), the probabilityof observing a chi-squared value <= X2 with v degrees of freedom.This is the probability that the sum of squares of v unit-variancenormally-distributed random variables is <= X2.Conversely:X2 = CHISQUARED_TABLE( P, v ) returns the X2, the value ofchi-squared corresponding to v degrees of freedom and probability P.In reference textbooks, what is normally tabulated are thepercentage points of the chi-squared distribution; thus, onewould use CHISQUARED_TABLE rather than interpolate such a table.References: Press et al., Numerical Recipes, Cambridge, 1986;Abramowitz & Stegun, Handbook of Mathematical Functions,Dover, 1972;  Table 26.8Peter R. ShawWoods Hole Oceanographic Institution, Woods Hole, MA 02543(508) 457-2000 ext. 2473pshaw@whoi.edu--FILES GENERATED--README_chisqchisquared_prob.m  (function) -- chi-squared probability functionchisquared_table.m  (function) -- "percentage points" (i.e., inverse)                                   of chi-squared probability functionchiaux.m (function) -- auxiliary fn. used by chisquared_table