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<TITLE>Formatting a Number in Exponential Notation
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<h3>
e313.
Formatting a Number in Exponential Notation</h3>
The `<code>E</code>' symbol specifies that a number should be formatted in
exponential notation. The symbol also separates the mantissa from the
exponent. The symbol must be followed by one or more `<code>0</code>' symbols. The
number of `<code>0</code>' symbols specifies the minimum number of digits used to
display the exponent.
<pre>
// Using only 0's to the left of E forces no decimal point
NumberFormat formatter = new DecimalFormat("0E0");
String s = formatter.format(<font color="#0066ff"><i>-1234.567</i></font>); // -1E3
formatter = new DecimalFormat("00E00");
s = formatter.format(<font color="#0066ff"><i>-1234.567</i></font>); // -12E02
formatter = new DecimalFormat("000E00");
s = formatter.format(<font color="#0066ff"><i>-1234.567</i></font>); // -123E01
formatter = new DecimalFormat("0000000000E0");
s = formatter.format(<font color="#0066ff"><i>-1234.567</i></font>); // -1234567000E-6
// Force minimum number of digits to left and right of decimal point
formatter = new DecimalFormat("0.0E0");
s = formatter.format(<font color="#0066ff"><i>-1234.567</i></font>); // -1.2E3
formatter = new DecimalFormat("00.00E0");
s = formatter.format(<font color="#0066ff"><i>-1234.567</i></font>); // -12.35E2
s = formatter.format(<font color="#0066ff"><i>-.1234567</i></font>); // -12.35E-2
// The number of #'s to the left of the decimal point (if any) specifies
// the multiple of the exponent. The total number of #'s (left and right)
// of the decimal point) specifies, the maximum number of digits to display
formatter = new DecimalFormat("#E0"); // exponent can be any value
s = formatter.format(<font color="#0066ff"><i>-1234.567</i></font>); // -.1E4
s = formatter.format(<font color="#0066ff"><i>-.1234567</i></font>); // -.1E0
formatter = new DecimalFormat("##E0"); // exponent must be multiple of 2
s = formatter.format(<font color="#0066ff"><i>-1234.567</i></font>); // -12E2
s = formatter.format(<font color="#0066ff"><i>-123.4567</i></font>); // -1.2E2
s = formatter.format(<font color="#0066ff"><i>-12.34567</i></font>); // -12E0
formatter = new DecimalFormat("###E0"); // exponent must be multiple of 3
s = formatter.format(<font color="#0066ff"><i>-1234.567</i></font>); // -1.23E3
s = formatter.format(<font color="#0066ff"><i>-123.4567</i></font>); // -123E0
s = formatter.format(<font color="#0066ff"><i>-12.34567</i></font>); // -12.3E0
s = formatter.format(<font color="#0066ff"><i>-1.234567</i></font>); // -12.3E0
s = formatter.format(<font color="#0066ff"><i>-.1234567</i></font>); // -123E-3
</pre>
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Related Examples
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e311. <a class="eglink" href="FormatNum.html?l=rel">
Formatting a Number Using a Custom Format
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e312. <a class="eglink" href="Numbers.html?l=rel">
Formatting and Parsing a Number for a Locale
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e314. <a class="eglink" href="Currency.html?l=rel">
Formatting and Parsing Locale-specific Currency
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e315. <a class="eglink" href="Percent.html?l=rel">
Formatting and Parsing a Locale-specific Percentage
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Dates
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Messsages
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<a class="eglink" href="/egs/java.text/pkg.html?l=rel#Times">
Times
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<a class="eglink" href="/egs/java.text/pkg.html?l=rel#Words%20and%20Sentences">
Words and Sentences
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