VBA Function Not Storing String [duplicate] - vba

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VBA Function not storing variable
Closed 5 years ago.
I am reposting this question, because I haven't gotten an answer and I still can't figure out what I'm doing wrong. My latest efforts to resolve the problem on my own are detailed below the code.
Original post: VBA Function not storing variable
I have included the code of my function. I mostly scrapped this together from things I found online, because I am very much an amateur coder. I am trying to take the trendline of a graph and use it for a mathematical calculation. When I step through this code, it works great. However, when I call the function from another sub, it gives me an error. Error 9: Subscript out of range. When I debug, it shows me the line a = spl(0). The real problem is that the variable "s" remains empty. Why?
Function TrendLineLog() As Double
Dim ch As Chart
Dim t As Trendline
Dim s As String
Dim Value As Double
' Get the trend line object
Set ch = ActiveSheet.ChartObjects(1).Chart
Set t = ch.SeriesCollection(1).Trendlines(1)
' make sure equation is displayed
t.DisplayRSquared = False
t.DisplayEquation = True
' set number format to ensure accuracy
t.DataLabel.NumberFormat = "0.000000E+00"
' get the equation
s = t.DataLabel.Text '<--------- ACTUAL PROBLEM HERE
' massage the equation string into form that will evaluate
s = Replace(s, "y = ", "")
s = Replace(s, "ln", " *LOG")
s = Replace(s, " +", "")
s = Replace(s, " - ", " -")
spl = Split(s, " ")
a = spl(0) '<----------- DEBUG SAYS HERE
b = spl(1)
c = spl(2)
y = 0.5
..... Math stuff
End Function
I have tried adding the creation of the chart to the function to avoid an error with "Active Sheet". I also tried pasting this code into my sub instead of calling a separate function. Still nothing. When I debug and highlight the t.DataLabel.Text, it shows me the correct value, but for some reason s is not saving that value. In the Locals window, t has value, but s is blank (" ").

Answer 1

Yes, of course you will get an error on the line you pointed out. You are calling spl(0) as though it is its own function, though you did not define spl() as a sub (function) anywhere in this code. Or, alternatively (more likely) you are calling it as an array, which also throws up some flags.
Make sure you are defining spl in your code. You never do this. Add line:
Dim spl(1 to 3) As String
Then you should find that spl(1), spl(2), and spl(3) are what you desire.