GAMMA Questions

Dear gamma users,
The relationship between unwrapped phase and the height should be:
phase = -[(4*pi*Bperp)/(λ*r*sinθ)]*height --equation(1)

(1)The program hgt_map can achieve this transformation.
For example, hgt_map $output.flt_sm.mcf.mask.unw1 $master.slc.par $output.off $output.base $output.height $output.grd 1
In this command, $output.flt_sm.mcf.mask.unw1 represents the unwrapped phase and $output.height represents the height.
I think phase./height should be equal to -[(4*pi*Bperp)/(λ*r*sinθ)] according to the equation (1) for each pixel.

(2)I also estimated the value of "-[(4*pi*Bperp)/(λ*r*sinθ)]" directly by substituting the specific value into this formula.
pi=3.14
Bperp is from the results of base_calc
λ is the wavelength
r is the value of center_range_slc from $master.slc.par
θ is the incidence angle

However, I found the results of "-[(4*pi*Bperp)/(λ*r*sinθ)]" are different calculated using these two different calculation ways. The result calculated through the first way is a matrix. Each pixel has a value of "[(4*pi*Bperp)/(λ*r*sinθ)]". The range of the values in matrix is from about -0.002 to -0.009.
And the result calculated through the second way is one value, which is -0.0519.

I don't know if these results are reasonable. I know that each pixel has its Bperp, r and θ. If I used these unique values of each pixel to calculate the exact result following the second way. Could I get the same results as those calculated through the first way? I think may be yes. But I am not sure.

Hope you can help me. Thank you so much.
Best regards,
Cynthia