Hi All,I have a function in C++ that takes in a variable length array (read in as something[]) as an argument. I have created a dll for the function and would like to call the function from Excel/VBA. My question regards the function declaration statement in VBA.I tried the following:Declare Function something Lib "c:\...." (x as Range) as doubleand that didn't work.I also tried:Declare Function something Lib "c:\...." (Paramarray x() as Variant) as doubleand that didn't work either.What is the right way to do this? ... I would greatly appreciate any help you might offer.Thank you,jabs

DCFC gave an excellent seminar on this last night. If you ask him really nicely then he might put his powerpoint slides online I guess... Too bad he can't put some more of that free beer online as well.

Hi JabsAll you have done could work. It depends on how you call the dll funciton you declared.If you useDeclare Function something Lib "c:\...." (Paramarray x() as Variant) as double... you should delcare an argument as Variant array. Somthing like:Dim arg_x() as VariantDim result as doubleresult = something(arg_x)Doing this, you will have no problem with arguments.

hianother way would be passing the first element of the array by reference(and the size of the array as another argument)Declare Function something Lib "c:\...." (x as double) as double...Dim a(0 to 9) as doubleDim result as doubleresult = something(a(0))referencehttp://support.microsoft.com/default.aspx?scid=http://support.microsoft.com:80/support ... bContent=1 edit: address of the reference should be all in one line

I've uploaded my notes.Any questions, please post in the Software forum.

Many thanks to DCFC, Student, luizvs and Cppfriend for all their help. Student's web link provided a solution that worked well for my particular problem. I will also check out DCFC's notes as he was kind enough to post them.Thanks again,Jabs

HiJust a question, I searched the site for the upload area without results.where can I find this uploadthx in advance

it's here

Hi all,This is a really emergency problem. I have been stuck here for three days, and I need to get my job done.I am trying to pass an array of string in VBA/EXCEL to a DLL. However, in my DLL, it's a function accepting parameters of Variant type.So the array is been passed as Variant into the DLL.The problem is it's not been recognized as any type. It's been treated as trash variable.Does any one have any clue about what can I do??Please help....Thanks a lot

I take it you've sussed out the MS documentation is maliciously wrong ?Declare Sub Stringer Lib "util.dll" (v As Variant) dim v as variantv = Array("thing", "other thing", "third thing", "not any of the other things")void __stdcall Stringer (VARIANT *v){ CString vbStuff; long index; VARIANT myv; for (index = v->parray->rgsabound->lLbound; index != v->parray->rgsabound->lLbound + v->parray->rgsabound->cElements; index++) { SafeArrayGetElement(v->parray, &index, &myv); vbStuff =myv.bstrVal; TRACE1("%s\n",vbStuff); } }

does anyone have a C++ to Excel dll example which uses Crank Nicolsen to price e.g. vanillas/ExoticsI wrote sth a while back to do just this, but ran into memory problems when the size of the discretizations in the mesh became small

No I don't have code for this, but it shouldn't be too hard unless your mesh is pathologically small.I suspect you memory problem was more to do with stack than free store. Excel has a limited stack, but you can fix this if you really want to.Although I've not seen your code, I rather feel that your architectiure for C-N is not optimal, if you're making multiple eval calls.This looks like the ideal candidate for a separate process.

thx ... can u recommend a good textbook or website which explains how to fix these kinda problems - I'm better at Maths than I am at fixing memory leakageM

Do we know it is a memory leak, or that you're allocating a structure too big to fit ?

Here is some thing I have done