Edition 7.0The DLL

Introduction

• A look at what’s new in the Dll

• A brief glimpse at “Dll Hell” and how you might minimize your time there

• A look at some development environments

• A look at some applications

• How you get your own copy of the Dll

• What the future holds…

What’s New

• The Dll now uses the same code as the console version, so the results are identical.

• There are new species in the SMC and NWO version.

• Data supporting the growth equations in the SWO version includes old-growth stands and stands with more hardwoods.

• Lahey FORTRAN compiler (version 9.5) used to generate the files

Why Dll ?

• Link free solution

• Simplicity, clarity, and completeness

• Larger problems can be considered

• Larger spatial regions can be considered

• Consistent platform

Organization

• Three separate files– ORGEDIT: (prepare) data imputation– ORGRUN: (execute) project tree lists– ORGVOL: (volcal) Estimate volume

• They use Microsoft PE/COFF (Portable Executable Common Object File Format)

• They use Microsoft Visual Basic name decorating

Dll “Hell”

• DLL Hell is an official Microsoft term gleaned from their developer network (they would know, they invented it!)

• COFF (originally from DEC) has been modified by Microsoft for WinNT 3 and it continues to change (PE/COFF)– Routines prior to Visual “stuff” 6 will need to “convert” the ‘lib’

• Calling routines ‘decorate’ function and subroutine names in called Dll’s– Familiarize yourself with your environments calling protocols– Use “Alias” to convert names.– Use standard call

• Microsoft compliant lib’s are included but with the infinitude of compilers out there you may need another

More Hell

• Intel defined an object file standard ‘OMF’ Object Model format.– If your environment uses it you will need to

convert coff2omf should work – unless it is old then you will need to use the

utility “convert”– Borland’s Builder and Delphi also use OMF

Even More Hell

• Name decoration:– Borland utility TDUMP will give the names inside of

the DLL– Dumpbin is Microsoft’s solution– More feature rich programs: PEBrowse, dumpbinGUI,

etc.

• After all of this, your compiler will use its own decoration protocol to call the Dll– Read the instructions (really)

• MS Visual Basic seems to have a benign protocol so we chose to use that one

And Even More Hell

• Security? There isn’t any!– We don’t include viruses, really!– We don’t format hard drives

• VB solves some problems but causes others– Relatively minor things will break your code

• VB blames almost every problem on calling convention

• It is nearly always lying!

“Bad Dll Calling Convention”

• Get used to seeing this!• From this you might infer that there is something

wrong with your Dll– There isn’t, its your application

• It means that the stack is confused• Why?

– Optimization for speed will put memory on 4 byte boundaries, sometimes…

– Change in compiler conventions

• No optimization selected in producing the Dll

Tested Environments

• Lahey FORTRAN and C– Version 5

• Microsoft Visual Studio– .NET

• Microsoft Office applications– Office 2003

• Borland’s Builder– Version 5– Version 6

• Intel FORTRAN

A few forestry details

• No management is included, but the effects are modeled– The user is responsible for filling the management

arrays– Fertilization

• Intensity (pounds of nitrogen)• Timing (both prior and post)• Maximum of 5 fertilizer applications

– Thinning• Intensity (basal area removed)• Timing (both prior and post)• Maximum of 5 thins

Applications

• A simple FORTRAN application

• Spreadsheet

• Access Database (?)

• R (?)

FORTRAN

FORTRAN

• Import function with DLL_IMPORT

• Get the name right with Alias– CDEC$ ATTRIBUTES, ALIAS:'_EXECUTE' ::

EXECUTE

• Alias helps in other environments

The dreaded Office

• This environment is very complex• This environment is constantly changing• Don’t go here! It is evil! The dark side will

draw you in and then it will crush you!• Hire a psychologist, if you don’t get over

your desire then hire a programmer• BIG ASTERIX (*)

– What you are about to see works in Office 2003 and probably no where else

EXCEL

EXCEL

• This design borrowed from Jeff Hamann

• But the mistakes are courtesy of me

• Jeff is much too smart to this

• Use ‘R’ it is the future

• Or even better just do it in FORTRAN

EXCEL

EXCEL

EXCEL

EXCEL

Excel

The future

• Seeking testers and example generators• Examples will be posted to the ORGANON

web site• FORSight Resources is building a

replacement for the console version• Additional utilities supporting the program

– Wrapper for the GMUG tree structure– Management routine

• What of .NET?

How to get a copy

• Send a request to:– ORGANON@OregonState.edu– Mark.Hanus@FORSightResources.com

The End

Questions?

Well I brought one…

• On average, what fraction of a square n times 2r on a side is covered by n-squared equal sized circles, of radius r, randomly distributed across it? The origin of all circles must fall in the square.