WSJT-X/lib/fitcal.f90

35 lines
602 B
Fortran

subroutine fitcal(x,y,r,iz,a,b,sigmaa,sigmab,rms)
implicit real*8 (a-h,o-z)
real*8 x(iz),y(iz),r(iz)
sx=0.d0
sy=0.d0
sxy=0.d0
sx2=0.d0
do i=1,iz
sx=sx + x(i)
sy=sy + y(i)
sxy=sxy + x(i)*y(i)
sx2=sx2 + x(i)*x(i)
enddo
delta=iz*sx2 - sx*sx
a=(sx2*sy - sx*sxy)/delta
b=(iz*sxy - sx*sy)/delta
sq=0.d0
do i=1,iz
r(i)=y(i) - (a + b*x(i))
sq=sq + r(i)**2
enddo
rms=0.
sigmaa=0.
sigmab=0.
if(iz.ge.3) then
rms=sqrt(sq/(iz-2))
sigmaa=sqrt(rms*rms*sx2/delta)
sigmab=sqrt(iz*rms*rms/delta)
endif
return
end subroutine fitcal