Talk:Scientific notation

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[edit] Standard index notation

The name I've always been taught is something like 'standard index notation'.

If you don't remember what it was then the teaching must have been rather ineffective. Are you sure it wasn't "index standard anecdotal notation"?

'Scientific notation' seems a bit vague - aren't there many other scientific notations?

It is a fairly commonly understood phrase. Yes there are many other scientific notations, but are there any that could be referred to without qualification? – Smyth 15:34, 9 Oct 2004 (UTC)

[edit] suggested paragraph

Should the following paragraph (or parts of) from Floating point be put on this page?

In other words, we could represent a number a by two numbers m and e, such that a = m × be. In any such system we pick a base b (called the base of numeration, also radix) and a precision p (how many digits to store). m (which is called the mantissa, also significand) is a p digit number of the form +-d.ddd...ddd (each digit being an integer between 0 and b-1 inclusive). If the leading digit of m is non-zero then the number is said to be normalised.

[edit] breaking quantities

If we follow a convention of writing 1.2E31 instead we can avoid the problem of having a break in the quanity...1.2 x

1031 Pizza Puzzle

You can force quantities to break as one word with the "non-breaking space" ( ): 1.2 × 1031. Besides, 1.2E31 is very ugly "calculator notation". I nearly cried when I saw someone use it on his math test paper. – Boudewijn 1 July 2005 12:12 (UTC)
1.2E31 is incorrect, as stated on this page. Fresheneesz 04:13, 15 September 2006 (UTC)

[edit] Cleaning Up

What needs cleaning up about this article? Lochok 04:03, 14 November 2005 (UTC)

It's not as bad as when the request was orginally made, but there are still a proliferation of one sentence paragraphs and I usually find a couple typos or redundancies everytime I look at it. It is much better now. The label can probably go soon. Jmeppley 22:21, 14 November 2005 (UTC)

[edit] parenthesis notation

Should also explain parenthesis notation indicating error, e.g., "1.345(67)".

[edit] Fortran

In Fortran, I recall that their exponential notation sometimes uses a 'd' instead of 'e'. For example, a number might be written as 1.234d-4 meaning the same thing as 1.234 * 10^-4 . I could have been incorrectly informed, but I think this would be a nice note on this page if someone can find a source for it (I looked quickly, but didn't find anything). Fresheneesz 04:10, 15 September 2006 (UTC)

From the Nastran 77 Standard (http://www.fortran.com/F77_std/rjcnf-4.html#sh-4.5)
4.5.1 Double Precision Exponent.
The form of a double precision exponent is the letter D followed by an optionally signed integer constant. A double precision exponent denotes a power of ten. Note that the form and interpretation of a double precision exponent are identical to those of a real exponent, except that the letter D is used instead of the letter E.
Nastran uses the letter D to denote double precision instead of the single precision (or float) data type. Thus, this is an artifact of Nastran syntax. Jebix

[edit] Normalised form

Re the 3rd paragraph - i believe it should read as follows:

  • In normalized form, b is chosen such that 1 \le \left | a \right \vert < 10

rather than "a is chosen". Given a number we wish to represent in normalised form, the |a| value is determined (mod a power of 10) - there is nothing to choose. We choose b so that a has the desired magnitude, not the other way round.

I changed this yesterday, but it was reverted by 75.35.109.215 with no comment. Before I put it back, would any one like to comment? JoeKearney 21:17, 18 January 2007 (UTC)


Since there has been noting said here for ten days I've changed it back. Please discuss here if you think it's wrong rather than just re-editing it. JoeKearney 01:09, 29 January 2007 (UTC)

[edit] Standard form?

I thought that was the entire number, ie-

6,765

instead of

6.765*10^3

DarkestMoonlight (talk) 16:15, 17 March 2008 (UTC)

Sorry, you thought wrong, for example: http://www.gcse.com/maths/standard_form.htm - 81.138.169.201 (talk) 15:49, 7 April 2008 (UTC)

In this same section, the exponents are not showing in my ie browser (but I don't know how to fix this on the page. can someone else? 5.72×10^9 shows up as 5.72×10 −6.1×10^−9 shows up as −6.1×10 —Preceding unsigned comment added by Mjvais (talk • contribs) 15:24, 22 April 2008 (UTC)

[edit] Isn't that backwards?

(Normalized) scientific notation is often called exponential notation...

AFAIK, "exponential notation" is generic, while "scientific notation" specifically refers to the one normalized so that the mantissa is in [1, 10), and "engineering notation" to the one normalized so that the mantissa is in [1, 1000) and the exponent is an integer multiple of three. Is that correct? --Army1987 (talk) 13:02, 9 June 2008 (UTC)