[Solved] VBA Function not running

Hello all, I started using VBA about 2 days ago and have no prior programming experience. I was programming the Newton Raphson method, an iterative procedure, in order to calculate data for a chemical process. Whenever I hit the green Run button, nothing happens other than the Macros menu opening. If I hit F8 to do the code step by step, nothing happens as well. I'm obviously missing something obvious, could someone please help me out? I would greatly appreciate it

Here is the code:

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You have created Functions and I suspect you need Subroutines. That's why a) they don't appear in the macro list and b) you can't step through them in the VBA Editor.


Regards, TMS

Whenever I hit the green Run button, nothing happens other than the Macros menu opening. If I hit F8 to do the code step by step, nothing happens as well. I'm obviously missing something obvious, could someone please help me out?

These methods of calling a procedure do not allow you to pass an argument to the procedure. You have written all of these functions to require an argument. As TMS suggests, you need a master Sub() procedure to call these functions with an appropriate argument, or you need to call these functions from a spreadsheet cell to pass an appropriate argument. Examples

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or in a spreadsheet cell =iteration(24). In order to enter debug mode, you will need to set a breakpoint somewhere in the function, so that the function will pause and let you inspect what is happening.

I note that you have v dim'ed twice in iteration -- once in the DIM statement and once in the function's argument list. I cannot remember for certain, but that may cause an error. You may also have issues with the scope of the various z and k variables, as they appear to only be dimensioned for the iteration procedure, but may not carry their values over to the other functions called by iteration.

I tend to prefer to code something like this as a UDF, so that I can call the function from the spreadsheet. With that in mind, I suggest a few pages for research and review:
http://www.cpearson.com/Excel/Writin...ionsInVBA.aspx
http://www.cpearson.com/Excel/DebuggingVBA.aspx
http://www.cpearson.com/Excel/Writin...ionsInVBA.aspx

EDIT: Got everything working perfectly, thanks again to you guys for helping out

Hey, I rewrote the code and everything seems to be working fine. However, I cannot get to the final answer which I am given, 0.201376. Rather, I get -2.308388. It's extremely frustrating as I am practically 100% sure my code is correct.

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Glad you got it figured out. If that resolves this problem, then please mark your thread as Solved (Edit first post).