from scipy import sum, mean, std, sqrt, absolute, array
import scipy.stats as st

f=array([[42,28,3],[17,89,21]])
r,c=f.shape
df=(r-1)*(c-1)
n=f.sum()

rs=sum(f,1)
cs=sum(f,0)
fcs=array([ cs*v for v in rs])/n
chi2=sum( (f-fcs)**2 / fcs)
alfa=0.90
cf=st.chi2.ppf(1-alfa,df) # egyoldali! csak 1-alfa kell!
print(chi2,"?",cf)