VBA Custom Function Celsius to Fahrenheit and vice versa

[brian662]

Hi, I have two functions, one called CtoF and the other called FtoC. As you might expect, one function converts temperatures from Centigrade to Fahrenheit, the other from Fahrenheit to Centrigrade.

The formulas I need to be able to do the conversion are:

Tc = (5/9)*(Tf-32)
Tf = (9/5)*Tc+32

(Tc = temperature in degrees Celsius, Tf = temperature in degrees Fahrenheit)

I am looking to write the code so that you can check for invalid data and perform other actions before carrying out the conversion.

I know to get started, I will probably want to place a function declaration like

Function CtoF(sngFar As Single) As Single
End Function

But where do I go from here??

I would much appreciate the help

 

[gsistek]

Try:

Function CtoF(sngFar As Single) As Single
    On Error Goto ErrorHandler
    CtoF = (9 / 5) * sngFar + 32
    Exit Function
ErrorHandler:
    'Replace with whatever you want to happen when it errors.
    Msgbox "ERROR!"
    CtoF = CVErr(xlErrValue)
End Function

 

[Jonmo1]

You might try the built in function called CONVERT

=CONVERT(A1,"C","F") <-Celcius to Fahrenheit
=CONVERT(A1,"F","C") <-Fahrenheit to Celcius