# Form number field decimals based on a second field

An expert helped me a while back with this topic but for some reason it is not working as I thought it was.

I have two fields on a form.  The first one is named "txtC_SIG_FIG" and is a number field and the data entered into this field is always a whole number with no decimals.  The 2nd one is named "txtC_MIN".  When a number is entered into the 2nd field I want it to carry out to the number of decimals entered in the 1st field.

So, for example, if txtC_SIG_FIG is 3, and if I enter 1.23412 in the 2nd field, I want the result in the 2nd field to display as 1.234

But if the value in txtC_SIG_FIG is 4, and if I enter 1.23412 in the 2nd field, I want the result in the 2nd field to display as 1.2341

Note:  The properties of the 2nd field in the table and on the form is Standard, auto decimals.

The current code which is not working is:

Me.txtC_MIN = Format([txtC_MIN], "0." & Right(10 ^ [txtC_SIG_FIG], Len(10 ^ [txtC_SIG_FIG]) - 1))
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Commented:
Here's a function I found some place.  I didn't write it and I'm sorry I don't remember who did.

``````Function RoundToNearest(dblNumber As Double, varRoundAmount As Double, _
Optional varUp As Variant) As Double

'''The following example creates a user-defined function called RoundToNearest, which accepts three parameters:
'''
'''dblNumber        The numeric value you want to round
'''varRoundAmount   The increment to which dblNumber will be rounded
'''varUp            An optional argument: include to round up; omit to round down
''' For example:
''''•RoundToNearest(3.33, 0.1, up) returns the value 3.4.'
''''•RoundToNearest(3.33, 0.1) returns the value 3.3.
''''.RoundToNearest(3.45678, 0.001) returns the value 3.456.
''''•RoundToNearest(3.33, 1, up) returns the value 4.'
''''•RoundToNearest(3.33, 1) returns the value 3.

Dim dblTemp As Double
Dim intTemp As Integer

dblTemp = dblNumber / varRoundAmount
intTemp = Int(dblTemp)

If intTemp = dblTemp Then
RoundToNearest = dblNumber
Else
If IsMissing(varUp) Then
' round down
dblTemp = intTemp
Else
' round up
dblTemp = intTemp + 1
End If
RoundToNearest = dblTemp * varRoundAmount
End If
End Function
``````

print roundtonearest(3.45678, .001)
3.456
0
Database DeveloperCommented:
This treats it like text, searching for the "." and moving the appropriate number of places past that:
``````=LEFT(TEXT(txtC_MIN,"#.############"), SEARCH(".",txtC_MIN)+txtC_SIG_FIG)
``````
0
CIOCommented:
This truncates the decimals while performing a 4/5 rounding:

Me.txtC_MIN  = Format([txtC_MIN], "0." & String([txtC_SIG_FIG], "0"))

/gustav
0
Author Commented:
I think we're getting close.  If I enter 1.12345 and the decimal qualifier is 3 I get 1.123  -  Perfect.

But if I enter 1.1 I get 1.1 and want to see 1.100

In other words, the number of decimals shown should always be the decimal qualifier (txtC_SIG_FIG)

????
0
CIOCommented:
Then you'll have to adjust the Format property of the textbox as well:

Me.txtC_MIN.Format  = "0." & String([txtC_SIG_FIG], "0")

/gustav
0
Author Commented:
Once more..  this is working great...

Me.txtC_MIN.Format  = "0." & String([txtC_SIG_FIG], "0")

But if the decimal qualifier is "0" and I enter 1 I am getting "1." (with the decimal.

Is there a way to get rid of the decimal if I enter a whole number and the qualifier is "0"?
0
CIOCommented:
Yes, though not very smart:

Me.txtC_MIN  = Format([txtC_MIN], "0" & Left(".", [txtC_SIG_FIG]) & String([txtC_SIG_FIG], "0"))
Me.txtC_MIN.Format  = "0" & Left(".", [txtC_SIG_FIG]) & String([txtC_SIG_FIG], "0")

/gustav
0

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