Approximatrix Forums — Apparent Allocation error

Re: Apparent Allocation error

null@example.com (Don Hazlewood) — Tue, 28 Jul 2015 20:24:02 +0000

Jeff,
Apparently there can only be one allocated array within a structure. The array Hout%HydCtl() is also being corrupted and gets set to the same value that is assigned to Hout%Hyd(?) Hope this helps.
Don

Re: Apparent Allocation error

null@example.com (Don Hazlewood) — Mon, 27 Jul 2015 23:43:52 +0000

Hi Jeff.
I tried changing the structure, ie, separating the Hyd and Elev statements so they aren't adjacent, but that didn't help. I've been programming for over 50 years and I've never run into something like this.

One other thing I need to check that I just thought of. I need to check HydCtl to see if it gets corrupted also. Will let you know.

Don

Re: Apparent Allocation error

null@example.com (jeff) — Sun, 26 Jul 2015 22:24:02 +0000

Don,

I'll have to research this behavior a bit. At first glance, I don't see an issue, of course. I'll see if I can reproduce the behavior.

Re: Apparent Allocation error

null@example.com (Don Hazlewood) — Sun, 26 Jul 2015 16:50:38 +0000

Hi Jeff. Found a work around. If I remove Elev from the Hout structure and make it a stand-alone array, the problem goes away. As I say, it's a work-around, not a solution. Here is the entire Hout structure:

Type Hydro_Out
Real(8), Allocatable :: Hyd(:) ! Outflow Hydrograph
! Real(8), Allocatable :: Elev(:) ! Outflow elevations at discharges
Real(8), Allocatable :: HydCtl(:) ! Hydraulic Control computed in QBreach
Real(8) :: DeltaT ! Time increment of hydrograph
Real(8) :: StartTime ! Starting time of first non-zero hydrograph value
Real(8) :: PeakQ ! Peak of the outflow hydrograph
Real(8) :: TimeQ ! Time of peak, outflow hydrograph
Real(8) :: Duration ! Duration of flow, outflow hydrograph
Real(8) :: StorVol ! Storage volume, ac. ft. of outflow hydrograph
Integer(4) :: nHydPts ! Number of points in the outflow hydrograph
Integer(4) :: nPeak ! Hydrograph pointer to peak
Character(10) :: HydID ! Hydrograph Identifier
End Type Hydro_Out
Type (Hydro_Out) :: Hout
Real(8), Allocatable :: ElevOut(:) ! Outflow elevations at discharges

Notice that Elev is commented out and ElevOut is its replacement.

Re: Apparent Allocation error

null@example.com (Don Hazlewood) — Sat, 25 Jul 2015 15:13:21 +0000

More info. I had an associate compile the program using the old Compaq Fortran and we get the same results. So it appears to be something in the code that's causing the problem. Is it possible that some type of optimization is the culprit?

Don

Apparent Allocation error

null@example.com (Don Hazlewood) — Fri, 24 Jul 2015 21:38:56 +0000

Jeff, I have found a problem that has me completely stumped. Following is a code snippet starting at line 783 in WinDam.f90:

! set initial input
Qin1 = Hin%Hyd(1)
! initialize time integral values and stored values
Hout%Hyd(1) = Qout1
EmbIntgrl(1) = 0.
Time = T1
Hout%Elev(1) = Elev1
EmbTime(1) = Time

Qout1 has a value of 4821. When Hout%Hyd(1) is set to Qout1, Hout%Elev(1) is also set to the same value and the assignment Hout%Elev(1) = Elev1 never happens. It's as if Hout%Hyd and Hout%Elev are allocated to the same space.

I can send you the entire program and dataset that's causing the problem if you want. The program consists of a mainline (WinDAM.f90) and approximately 60 modules and subroutines. Just tell me your email and I'll send it to you.

Don