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Re: How to use decimal format.

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On Tuesday, 18 April 2000 at 03:00:00 UTC-4, Yun Mo wrote:
> With the format "##0.##E00" and method of myformat, I got:
> a=0.01 formatted=+1E-03
> a=-100600.0 formatted=-100.6E+03
> a=-100500.0 formatted=-100.5E+03
> a=-100510.0 formatted=-100.51E+03
> a=-100500.0000000001 formatted=-100.5E+03
> a=0.0 formatted= 0E+00
> a=-1230.0 formatted=-1.23E+03
> a=99999.99951 formatted=+1E+03
> b=100000 formatted=+1E+03
> With "0.00E00" and the method of myformat, I obtained:
> a=0.01 formatted=+1.00E-02
> a=-100600.0 formatted=-1.01E+05
> a=-100500.0 formatted=-1.00E+05 (x)
> a=-100510.0 formatted=-1.01E+05 (ok)
> a=-100500.0000000001 formatted=-1.01E+05 (ok)
> a=0.0 formatted= 0.00E+00
> a=-1230.0 formatted=-1.23E+03
> a=99999.99951 formatted=+1.00E+05
> b=100000 formatted=+1.00E+05
> 
> It seems that no problem for the fixed decimal format like "0.00E00".
> Of course, there exists a worry about formatting 100500 with "0.00E00".
> In engineering, we only want some number of valid digits.
> The following format is a despoit result. The reason may be that it
> takes digit from right side of 100,000.
> At lease, the maximum integer digits should larger than 6.
> I dont't know the exact reason that it could get the expected result with "0.00E00".
> But it can guess that it takes digits from left side of 100,00 for "0.00E00".
> > java.text.DecimalFormat df =
> > (java.text.DecimalFormat)java.text.NumberFormat.getInstance();
> > df.setMaximumIntegerDigits(3);
> > System.out.println(df.format(99999.99951));//should at least throw an
> //exception, gives 000
> Dirk Bosmans wrote:
> > And don't use java.text.DecimalFormat with exponent notations. Try this one:
> >
> > java.text.DecimalFormat df = new java.text.DecimalFormat("##0.###E0");
> > System.out.println(df.format(99999.99951));//should be 100E3, gives 1E3
> >
> > Dangerous. And what about fixed point? Do you like loosing most-significand
> > digits without a warning?
> >
> > java.text.DecimalFormat df =
> > (java.text.DecimalFormat)java.text.NumberFormat.getInstance();
> > df.setMaximumIntegerDigits(3);
> > System.out.println(df.format(99999.99951));//should at least throw an
> > //exception, gives 000
> >
> > I'm reacting to following parts of Patricia Shanahan <pa...@acm.org>'s article in
> > comp.lang.java.help on 17 Apr 2000 09:31:08 EDT6
> >
> > ....
> > . If numbers that happen to be exactly representable in decimal are
> > . particularly important in your program use BigDecimal instead of double.
> > . Even if double is right for your general arithmetic, if you want a
> > . different rounding mode from round half even convert to BigDecimal
> > . before display, use BigDecimal to do the formatting.
> > .
> > . Patricia
> >
> > Greetings,
> > Dirk Bosmans
> >
> > http://users.belgacombusiness.net/arci/
> > - Applicet Framework: turns Applets into Applications
> > - ArciMath BigDecimal: now with BigDecimalFormat
u a bot and a loser

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Re: How to use decimal format. Little Ninja <majdfaqir2010@gmail.com> - 2020-11-18 17:35 -0800

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