Where do you want to use the Cosine, Sine and FFT functionality? In Excel cell forumla or just in Excel VBA?
If you want to use COS and SIN, I think both in Excel cell and in VBA we can use it natively, for ex, in an Excel cell, we can type "=COS(A1)", here A1 refers to another cell that has the column number A and row number 1. In VBA environment, I think the Visual Basic language support the COS and SIN natively, too, you can type A = COS(B) or something to do it.
Anyway, please tell me how you want to use such functions in your project, or are you just wanting to implement another copy of COS and SIN instead of the native ones?
Hopefully, you'll be able to get back to us with more details, but the engineer did have some general suggestions:
I have reviewed the link. However, I am not very sure if the customer means Excel or PowerPoint. He wants to change background colour of a graph in a Powerpoint slide through a Macro command, or modify any kind of object in an organization chart.
If you can perform the operation successfully manually (through GUI, not code), I think we can record the operations into a macro, using the following steps:
1. In PowerPoint, click Tools | Macro | Record New Macro. Create a new macro.
2. Perform the operation.
3. Stop recording macro.
4. Press Alt + F11 to check the macro code.
Please notice not all operations can be recorded. But we can just try.