;
; SUMMATIONS Phir=dPhi/dr,Phith=dPhi/dth,and Phiph=dPhi/dphi
; Hr & dHr include the effect of various models
; NOTE: apar is useless   10May2000
;
pro brtp,Nmax,apar,r,sthi,Hr,dHr,Pi,dPi,Gfj,dGfj,Br,Bt,Bp

    Phir = double(0.0)
    Phith = double(0.0)
    Phiph = double(0.0)
    for n=0, Nmax do begin
        for m=0, n do begin
            Phir= Phir + dHr(n)*Pi(n,m)*Gfj(n,m)
            Phith= Phith + Hr(n)*dPi(n,m)*Gfj(n,m)
            Phiph= Phiph + Hr(n)*Pi(n,m)*dGfj(n,m)
        endfor
    endfor
   ;Br = -1.* (1 + apar/r)^2 * Phir
    Br = -1.* Phir    ; corrected on Apr. 3, 1998
    Bt = -1.* Phith/r
    Bp = -1.* Phiph/r/sthi

end