Floating overflow in function flow_depth (hydraulic.f90)

[BernardoTeufel]

The following code causes floating overflow crash for extremely small Qin values (e.g., 2.e-114):

mizuRoute/route/build/src/hydraulic.f90

Line 409 in 64a49b0

Coef1 = (sqrt(S)/n/Qin)**3

Solved by changing the following line to: if (Qin>1.e-50_dp) then

mizuRoute/route/build/src/hydraulic.f90

Line 356 in 64a49b0

if (Qin>0._dp) then

Choice of 1.e-50_dp was based on the value used here:

mizuRoute/route/build/src/tracer.f90

Line 291 in 64a49b0

if (abs(Qbar)>1.e-50_dp) then

An alternative could be 1.e-10_dp (unused variable so far):

mizuRoute/route/build/src/public_var.f90

Line 44 in 64a49b0

real(dp), parameter,public :: MinPosVal=1.e-10_dp ! minimum value for positive value

[nmizukami]

Hi Bernardo, I will need to sort this out. I did run into this problem before even before tracer was implemented. For 64bit, the smallest positive floating number can go even smaller than that