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functions in gammp.i - g

 
 
 
gammp


             gammp(a, x)  
         or gammp(a, x, q, lg)  
 
    return P(a,x) = int[0 to x]{ du * u^(a-1)*exp(-u) } / gamma(a)  
    optionally return Q(a,x) = 1-P(a,x) and ln(gamma(a))  
    
    Note that erf(x)=gammp(0.5,x^2) and erfc(x)=gammq(0.5,x^2)  
    Also P(chi2|nu)=gammp(0.5*nu,0.5*chi2)  
     and Q(chi2|nu)=gammq(0.5*nu,0.5*chi2)  
    are the probabilities that an observed chi-square be less than  
    or greater than (P or Q) chi2 when there are nu degrees of freedom  
    (terms in the chi-square sum).  
    
interpreted function, defined at i/gammp.i   line 14  
SEE ALSO: gammq,   betai,   ln_gamma  
 
 
 
gammq


             gammq(a, x)  
         or gammq(a, x, p, lg)  
 
    return Q(a,x) = 1 - int[0 to x]{ du * u^(a-1)*exp(-u) } / gamma(a)  
    optionally return P(a,x) = 1-Q(a,x) and ln(gamma(a))  
    
    Note that erf(x)=gammp(0.5,x^2) and erfc(x)=gammq(0.5,x^2)  
    Also P(chi2|nu)=gammp(0.5*nu,0.5*chi2)  
     and Q(chi2|nu)=gammq(0.5*nu,0.5*chi2)  
    are the probabilities that an observed chi-square be less than  
    or greater than (P or Q) chi2 when there are nu degrees of freedom  
    (terms in the chi-square sum).  
    
interpreted function, defined at i/gammp.i   line 50  
SEE ALSO: gammp,   betai,   ln_gamma