Still celebrating National IT Professionals Day with 3 months of free Premium Membership. Use Code ITDAY17

x
?
Solved

VB Significant Digits function

Posted on 2003-11-09
8
Medium Priority
?
902 Views
Last Modified: 2010-08-05
Does anyone have a visual basic function that will return a passed number with a requested number of significant digits?
For example:
X = 1.233412
Y = FixSigFigs(X,3) 'I want Y to have 3 significant digits.

Function FixSigFigs( NumberToFix as double, SigFigs as Integer)

0
Comment
Question by:kar8942
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
8 Comments
 
LVL 48

Assisted Solution

by:AlexFM
AlexFM earned 249 total points
ID: 9709953
Round Function

Returns a number rounded to a specified number of decimal places.
Round(expression [,numdecimalplaces])

Dim MyVar, pi
pi = 3.14159
MyVar = Round(pi, 2) ' MyVar contains 3.14.

0
 
LVL 86

Assisted Solution

by:Mike Tomlinson
Mike Tomlinson earned 249 total points
ID: 9709955
Public Function FixSigFigs(NumberToFix As Double, SigFigs As Integer) As Double
    Dim textNumber As String
    Dim decimalPlace As Integer
    Dim digitsToRight As Integer
   
    FixSigFigs = NumberToFix ' If no change, return original number
    textNumber = CStr(NumberToFix)
    decimalPlace = InStr(textNumber, ".")
    If decimalPlace > 0 Then
        digitsToRight = Len(textNumber) - decimalPlace
        If digitsToRight > SigFigs And SigFigs >= 0 Then
            FixSigFigs = CDbl(Left(textNumber, decimalPlace + SigFigs))
        End If
    End If
End Function
0
 
LVL 86

Expert Comment

by:Mike Tomlinson
ID: 9710584
You didn't specify as to whether you wanted rounding or not.  Use the Round() function, as AlexFM suggested, if you need rounding to occur.  Otherwise, use my function if you simply want to truncate the number to the requested number of digits.
0
Concerto Cloud for Software Providers & ISVs

Can Concerto Cloud Services help you focus on evolving your application offerings, while delivering the best cloud experience to your customers? From DevOps to revenue models and customer support, the answer is yes!

Learn how Concerto can help you.

 
LVL 6

Accepted Solution

by:
VK earned 252 total points
ID: 9714620
hello kar8942 !

That isn't a simple task in general.
Of course you can use the built in round function of vb.
But this function isn't country-independent.

Example:

? round(1.145,2)
 1,14
? round(1.245,2)
 1,25

In germany for example round(1.145,2) should be 1.15.
Therefore i wrote a user defined function:

Public Function RoundIt(Number As Variant, ByVal NumDigitsAfterDecimal As Long) As Variant
    Select Case True
        Case Not IsNumeric(Number)
            RoundIt = Number
        Case Else
            NumDigitsAfterDecimal = 10 ^ NumDigitsAfterDecimal
            RoundIt = Int(CDec(CDec(0.5) + CDec(Number) * CDec(NumDigitsAfterDecimal))) / CDec(NumDigitsAfterDecimal)
    End Select
End Function

regards

V.K.
0
 
LVL 86

Expert Comment

by:Mike Tomlinson
ID: 9872472
What did you decide to use?
0
 
LVL 48

Expert Comment

by:AlexFM
ID: 10163002
kar8942 got two ways: rounding and truncating. He should decide what he need. Without his response I think points should be splitted.
0
 

Author Comment

by:kar8942
ID: 10164264
Neither answer actually worked, but I will split the points anyway. Thanks.
0

Featured Post

Industry Leaders: We Want Your Opinion!

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Introduction In a recent article (http://www.experts-exchange.com/A_7811-A-Better-Concatenate-Function.html) for the Excel community, I showed an improved version of the Excel Concatenate() function.  While writing that article I realized that no o…
Background What I'm presenting in this article is the result of 2 conditions in my work area: We have a SQL Server production environment but no development or test environment; andWe have an MS Access front end using tables in SQL Server but we a…
As developers, we are not limited to the functions provided by the VBA language. In addition, we can call the functions that are part of the Windows operating system. These functions are part of the Windows API (Application Programming Interface). U…
Show developers how to use a criteria form to limit the data that appears on an Access report. It is a common requirement that users can specify the criteria for a report at runtime. The easiest way to accomplish this is using a criteria form that a…
Suggested Courses

715 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question