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asked 5 years ago viewed 1994 times active 2 years ago Visit Chat Linked 0 Calculation with rounded values in Excel 9 Why does CLng produce different results? 2 Why does Cheers, Patrick Reply With Quote Quick Navigation Code It Better Top Site Areas Settings Private Messages Subscriptions Who's Online Search Forums Forums Home Forums Visual Basic Visual Basic .NET VB.net CodeBank To turn on this option, follow these steps: Click Microsoft Office Button -> Excel Options -> Advanced In the When calculating this workbook section, select the workbook you want, and then In the third line, one is subtracted from the sum using Excel.

Appease Your Google Overlords: Draw the "G" Logo If Dumbledore is the most powerful wizard (allegedly), why would he work at a glorified boarding school? An example of this occurs in an sheet where the following cells are set to the following numeric values: A 1 := 28.552 {\displaystyle A1:=28.552} A 2 := 27.399 {\displaystyle A2:=27.399} This article describes and explains the causes for errors that are due to either of the causes described above: the displayed formatted number and the internal errors associated with floating point Computers store an integer (whole number) value as (x*1 + x*2 + x*4 + x*8 + x*16 etc) where x is the state of the bit.

Rick Rothstein (MVP - Excel) July 2, 2010 at 1:46 am Of course, if you want normal rounding inside of your own code, you can call out to the worksheet's ROUND For the reasoning behind the conversion to binary representation and back to decimal, and for more detail about accuracy in Excel and VBA consult these links.[9] Examples where precision is no Example: The number 10.4 can be expressed as a double precision floating point number as follows. The second is a computer design issue.

However, numerical inaccuracy still can be shown using this example by extending the existing figure to include 1015, whereupon the erroneous standard deviation found by Excel 2010 will be zero. Because each number has only fifteen significant digits, their difference is inaccurate when there aren't enough significant digits to express the difference. ^ Robert de Levie (2004). "Algorithmic accuracy". Hope you have some usefull tips for me. If this parameter is omitted, then the ROUND function will return an integer.

This is due to the fact that the IEEE 754 standard requires numbers to be stored in binary format. I have read this in Jonathan Allen's reply in VB6 rounding behavior Here is the result to the test: a = cDec(61048.4599674847) b = cDec(154553063.208822) c = a + b ?c This option applies to the entire workbook, not to a specific cell or range of cells.

Floating Point Numbers

Excel, like nearly every other computer program, uses the IEEE Standard Determine if a coin system is Canonical Why is the spacesuit design so strange in Sunshine?

If I use this: Code: =VBRoundError(99,true) excel displays 1.000000000000000000 =VBRoundError(999,true) excel displays 10.000000000000000000 =VBRoundError(9999,true) excel displays 100.000000000000000000 I get nice even values. Irrational numbers such as Ï€ or , or non-terminating rational numbers must be approximated. These formulas involve comparisons of adjacent values. Exploded Suffixes What is a type system?

You have checked over your calculations and still cannot figure out where it went wrong. Visual basic and arithmetic precision: Oriented toward VBA, which does things a bit differently. This is called an "unnormalized" number, and is how the value 0 is stored in a double. The bold portion is the exponent, and the rest is the mantissa.

However, the ROUND function behaves a little peculiar, so before using this function, please read the following: The ROUND function utilizes round-to-even logic. Here is the FAQ for this forum. + Reply to Thread Results 1 to 5 of 5 Worksheet rounding vs VBA rounding Thread Tools Show Printable Version Subscribe to this Thread… The Exponent The exponent stores the power of 2 to which the number is raised or lowered. Oxford University Press.

All rights reserved. My way around it is to have a function in a module that has the same name: Public Function Round(ByVal Number As Variant, Optional ByVal NumDigitsAfterDecimal As Integer = 0) As For example, the equation =1*(.5-.4-.1) may be evaluated to the quantity (-2.78E-17), or -0.0000000000000000278 instead of 0. Academic Press, Inc.

The first method is to use the ROUND() function. Thus, the numbers Excel calculates with are not the numbers that it displays. For example, a stored value of 1000 indicates an exponent of 1000 - 1023, or -23. Because the sum has only eleven 1's after the decimal, the true difference when ‘1’ is subtracted is three 0's followed by a string of eleven 1's.

BusinessDevHomeITNon-profitOn-premisesPartnerPublic sectorSchoolSmall BusinessClear allApply filtersWhat do you want to see? This is once again is because Excel stores 15 digits of precision. Excel stores numbers differently that you may have them formatted display on the worksheet. If I type these into cells within excel: Code: =VBRoundError(99) excel displays 1.000000000000000000 =VBRoundError(999) excel displays 9.999999999999830000 =VBRoundError(9999) excel displays 100.000000000014000000 You can clearly see that there is rounding error taking

There are generally two possible causes of this problem. For example, Format(2.5, "0?) or Format(2.5, "#"), depending on if you want to force zeroes or not, will round up to 3 as expected (at least, as expected by me). The first is that the numbers are not displayed to their full values. Same kind of problem surfaces with stopping criteria.

Note that this function permits the NumberOfDigits argument to be negative (similar to the worksheet's Round function). For example, both CLng(1.5) and CLng(2.5) will return 2 as the converted value because Banker's Rounding lies at the heart of the conversion. Frequently Asked Questions Question: I read your explanation of how the ROUND function works in VBA using the round-to-even logic. more stack exchange communities company blog Stack Exchange Inbox Reputation and Badges sign up log in tour help Tour Start here for a quick overview of the site Help Center Detailed

Translated by Scripta Technica, Inc. (8 ed.). Excel's storage of numbers in binary format also affects its accuracy.[4] To illustrate, the lower figure tabulates the simple addition 1 + x − 1 for several values of x. The bottom line is that in doing this calculation using Excel, as the roots become farther apart in value, the method of calculation will have to switch from direct evaluation of In the figure, Excel is used to find the smallest root of the quadratic equation x2+bx+c=0 for c=4 andc=4×105.

Members List Calendar Forum Rules Dashboard Commercial Services Advanced Search Forum Microsoft Office Application Help - Excel Help forum Excel Programming / VBA / Macros [SOLVED] Worksheet rounding vs VBA rounding The last two examples illustrate what happens if x is a rather small number. The IEEE 754 floating-point standard requires that numbers be stored in binary format. There really is no way around this because of the way VB/A works.

The bias of the exponent is 127 rather than 1023.

Register Help Forgotten Your Password? The other day when I was comparing values in Excel I used the =ROUND() function and was shocked to see my old friend, the \$0.01 difference.