Java Code Examples for sun.misc.DoubleConsts#MAX_EXPONENT
The following examples show how to use
sun.misc.DoubleConsts#MAX_EXPONENT .
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Example 1
| Source File: FpUtils.java From dragonwell8_jdk with GNU General Public License v2.0 | 4 votes |
|
/**
* Returns unbiased exponent of a {@code double}; for
* subnormal values, the number is treated as if it were
* normalized. That is for all finite, non-zero, positive numbers
* <i>x</i>, <code>scalb(<i>x</i>, -ilogb(<i>x</i>))</code> is
* always in the range [1, 2).
* <p>
* Special cases:
* <ul>
* <li> If the argument is NaN, then the result is 2<sup>30</sup>.
* <li> If the argument is infinite, then the result is 2<sup>28</sup>.
* <li> If the argument is zero, then the result is -(2<sup>28</sup>).
* </ul>
*
* @param d floating-point number whose exponent is to be extracted
* @return unbiased exponent of the argument.
* @author Joseph D. Darcy
*/
public static int ilogb(double d) {
int exponent = getExponent(d);
switch (exponent) {
case DoubleConsts.MAX_EXPONENT+1: // NaN or infinity
if( isNaN(d) )
return (1<<30); // 2^30
else // infinite value
return (1<<28); // 2^28
case DoubleConsts.MIN_EXPONENT-1: // zero or subnormal
if(d == 0.0) {
return -(1<<28); // -(2^28)
}
else {
long transducer = Double.doubleToRawLongBits(d);
/*
* To avoid causing slow arithmetic on subnormals,
* the scaling to determine when d's significand
* is normalized is done in integer arithmetic.
* (there must be at least one "1" bit in the
* significand since zero has been screened out.
*/
// isolate significand bits
transducer &= DoubleConsts.SIGNIF_BIT_MASK;
assert(transducer != 0L);
// This loop is simple and functional. We might be
// able to do something more clever that was faster;
// e.g. number of leading zero detection on
// (transducer << (# exponent and sign bits).
while (transducer <
(1L << (DoubleConsts.SIGNIFICAND_WIDTH - 1))) {
transducer *= 2;
exponent--;
}
exponent++;
assert( exponent >=
DoubleConsts.MIN_EXPONENT - (DoubleConsts.SIGNIFICAND_WIDTH-1) &&
exponent < DoubleConsts.MIN_EXPONENT);
return exponent;
}
default:
assert( exponent >= DoubleConsts.MIN_EXPONENT &&
exponent <= DoubleConsts.MAX_EXPONENT);
return exponent;
}
}
Example 2
| Source File: FpUtils.java From TencentKona-8 with GNU General Public License v2.0 | 4 votes |
|
/**
* Returns unbiased exponent of a {@code double}; for
* subnormal values, the number is treated as if it were
* normalized. That is for all finite, non-zero, positive numbers
* <i>x</i>, <code>scalb(<i>x</i>, -ilogb(<i>x</i>))</code> is
* always in the range [1, 2).
* <p>
* Special cases:
* <ul>
* <li> If the argument is NaN, then the result is 2<sup>30</sup>.
* <li> If the argument is infinite, then the result is 2<sup>28</sup>.
* <li> If the argument is zero, then the result is -(2<sup>28</sup>).
* </ul>
*
* @param d floating-point number whose exponent is to be extracted
* @return unbiased exponent of the argument.
* @author Joseph D. Darcy
*/
public static int ilogb(double d) {
int exponent = getExponent(d);
switch (exponent) {
case DoubleConsts.MAX_EXPONENT+1: // NaN or infinity
if( isNaN(d) )
return (1<<30); // 2^30
else // infinite value
return (1<<28); // 2^28
case DoubleConsts.MIN_EXPONENT-1: // zero or subnormal
if(d == 0.0) {
return -(1<<28); // -(2^28)
}
else {
long transducer = Double.doubleToRawLongBits(d);
/*
* To avoid causing slow arithmetic on subnormals,
* the scaling to determine when d's significand
* is normalized is done in integer arithmetic.
* (there must be at least one "1" bit in the
* significand since zero has been screened out.
*/
// isolate significand bits
transducer &= DoubleConsts.SIGNIF_BIT_MASK;
assert(transducer != 0L);
// This loop is simple and functional. We might be
// able to do something more clever that was faster;
// e.g. number of leading zero detection on
// (transducer << (# exponent and sign bits).
while (transducer <
(1L << (DoubleConsts.SIGNIFICAND_WIDTH - 1))) {
transducer *= 2;
exponent--;
}
exponent++;
assert( exponent >=
DoubleConsts.MIN_EXPONENT - (DoubleConsts.SIGNIFICAND_WIDTH-1) &&
exponent < DoubleConsts.MIN_EXPONENT);
return exponent;
}
default:
assert( exponent >= DoubleConsts.MIN_EXPONENT &&
exponent <= DoubleConsts.MAX_EXPONENT);
return exponent;
}
}
Example 3
| Source File: FpUtils.java From jdk8u60 with GNU General Public License v2.0 | 4 votes |
|
/**
* Returns unbiased exponent of a {@code double}; for
* subnormal values, the number is treated as if it were
* normalized. That is for all finite, non-zero, positive numbers
* <i>x</i>, <code>scalb(<i>x</i>, -ilogb(<i>x</i>))</code> is
* always in the range [1, 2).
* <p>
* Special cases:
* <ul>
* <li> If the argument is NaN, then the result is 2<sup>30</sup>.
* <li> If the argument is infinite, then the result is 2<sup>28</sup>.
* <li> If the argument is zero, then the result is -(2<sup>28</sup>).
* </ul>
*
* @param d floating-point number whose exponent is to be extracted
* @return unbiased exponent of the argument.
* @author Joseph D. Darcy
*/
public static int ilogb(double d) {
int exponent = getExponent(d);
switch (exponent) {
case DoubleConsts.MAX_EXPONENT+1: // NaN or infinity
if( isNaN(d) )
return (1<<30); // 2^30
else // infinite value
return (1<<28); // 2^28
case DoubleConsts.MIN_EXPONENT-1: // zero or subnormal
if(d == 0.0) {
return -(1<<28); // -(2^28)
}
else {
long transducer = Double.doubleToRawLongBits(d);
/*
* To avoid causing slow arithmetic on subnormals,
* the scaling to determine when d's significand
* is normalized is done in integer arithmetic.
* (there must be at least one "1" bit in the
* significand since zero has been screened out.
*/
// isolate significand bits
transducer &= DoubleConsts.SIGNIF_BIT_MASK;
assert(transducer != 0L);
// This loop is simple and functional. We might be
// able to do something more clever that was faster;
// e.g. number of leading zero detection on
// (transducer << (# exponent and sign bits).
while (transducer <
(1L << (DoubleConsts.SIGNIFICAND_WIDTH - 1))) {
transducer *= 2;
exponent--;
}
exponent++;
assert( exponent >=
DoubleConsts.MIN_EXPONENT - (DoubleConsts.SIGNIFICAND_WIDTH-1) &&
exponent < DoubleConsts.MIN_EXPONENT);
return exponent;
}
default:
assert( exponent >= DoubleConsts.MIN_EXPONENT &&
exponent <= DoubleConsts.MAX_EXPONENT);
return exponent;
}
}
Example 4
| Source File: FpUtils.java From java-n-IDE-for-Android with Apache License 2.0 | 4 votes |
|
/**
* Returns unbiased exponent of a <code>double</code>; for
* subnormal values, the number is treated as if it were
* normalized. That is for all finite, non-zero, positive numbers
* <i>x</i>, <code>scalb(<i>x</i>, -ilogb(<i>x</i>))</code> is
* always in the range [1, 2).
* <p>
* Special cases:
* <ul>
* <li> If the argument is NaN, then the result is 2<sup>30</sup>.
* <li> If the argument is infinite, then the result is 2<sup>28</sup>.
* <li> If the argument is zero, then the result is -(2<sup>28</sup>).
* </ul>
*
* @param d floating-point number whose exponent is to be extracted
* @return unbiased exponent of the argument.
* @author Joseph D. Darcy
*/
public static int ilogb(double d) {
int exponent = getExponent(d);
switch (exponent) {
case DoubleConsts.MAX_EXPONENT+1: // NaN or infinity
if( isNaN(d) )
return (1<<30); // 2^30
else // infinite value
return (1<<28); // 2^28
// break;
case DoubleConsts.MIN_EXPONENT-1: // zero or subnormal
if(d == 0.0) {
return -(1<<28); // -(2^28)
}
else {
long transducer = Double.doubleToRawLongBits(d);
/*
* To avoid causing slow arithmetic on subnormals,
* the scaling to determine when d's significand
* is normalized is done in integer arithmetic.
* (there must be at least one "1" bit in the
* significand since zero has been screened out.
*/
// isolate significand bits
transducer &= DoubleConsts.SIGNIF_BIT_MASK;
assert(transducer != 0L);
// This loop is simple and functional. We might be
// able to do something more clever that was faster;
// e.g. number of leading zero detection on
// (transducer << (# exponent and sign bits).
while (transducer <
(1L << (DoubleConsts.SIGNIFICAND_WIDTH - 1))) {
transducer *= 2;
exponent--;
}
exponent++;
assert( exponent >=
DoubleConsts.MIN_EXPONENT - (DoubleConsts.SIGNIFICAND_WIDTH-1) &&
exponent < DoubleConsts.MIN_EXPONENT);
return exponent;
}
// break;
default:
assert( exponent >= DoubleConsts.MIN_EXPONENT &&
exponent <= DoubleConsts.MAX_EXPONENT);
return exponent;
// break;
}
}
Example 5
| Source File: FpUtils.java From openjdk-jdk8u with GNU General Public License v2.0 | 4 votes |
|
/**
* Returns unbiased exponent of a {@code double}; for
* subnormal values, the number is treated as if it were
* normalized. That is for all finite, non-zero, positive numbers
* <i>x</i>, <code>scalb(<i>x</i>, -ilogb(<i>x</i>))</code> is
* always in the range [1, 2).
* <p>
* Special cases:
* <ul>
* <li> If the argument is NaN, then the result is 2<sup>30</sup>.
* <li> If the argument is infinite, then the result is 2<sup>28</sup>.
* <li> If the argument is zero, then the result is -(2<sup>28</sup>).
* </ul>
*
* @param d floating-point number whose exponent is to be extracted
* @return unbiased exponent of the argument.
* @author Joseph D. Darcy
*/
public static int ilogb(double d) {
int exponent = getExponent(d);
switch (exponent) {
case DoubleConsts.MAX_EXPONENT+1: // NaN or infinity
if( isNaN(d) )
return (1<<30); // 2^30
else // infinite value
return (1<<28); // 2^28
case DoubleConsts.MIN_EXPONENT-1: // zero or subnormal
if(d == 0.0) {
return -(1<<28); // -(2^28)
}
else {
long transducer = Double.doubleToRawLongBits(d);
/*
* To avoid causing slow arithmetic on subnormals,
* the scaling to determine when d's significand
* is normalized is done in integer arithmetic.
* (there must be at least one "1" bit in the
* significand since zero has been screened out.
*/
// isolate significand bits
transducer &= DoubleConsts.SIGNIF_BIT_MASK;
assert(transducer != 0L);
// This loop is simple and functional. We might be
// able to do something more clever that was faster;
// e.g. number of leading zero detection on
// (transducer << (# exponent and sign bits).
while (transducer <
(1L << (DoubleConsts.SIGNIFICAND_WIDTH - 1))) {
transducer *= 2;
exponent--;
}
exponent++;
assert( exponent >=
DoubleConsts.MIN_EXPONENT - (DoubleConsts.SIGNIFICAND_WIDTH-1) &&
exponent < DoubleConsts.MIN_EXPONENT);
return exponent;
}
default:
assert( exponent >= DoubleConsts.MIN_EXPONENT &&
exponent <= DoubleConsts.MAX_EXPONENT);
return exponent;
}
}
Example 6
| Source File: FpUtils.java From openjdk-jdk8u-backup with GNU General Public License v2.0 | 4 votes |
|
/**
* Returns unbiased exponent of a {@code double}; for
* subnormal values, the number is treated as if it were
* normalized. That is for all finite, non-zero, positive numbers
* <i>x</i>, <code>scalb(<i>x</i>, -ilogb(<i>x</i>))</code> is
* always in the range [1, 2).
* <p>
* Special cases:
* <ul>
* <li> If the argument is NaN, then the result is 2<sup>30</sup>.
* <li> If the argument is infinite, then the result is 2<sup>28</sup>.
* <li> If the argument is zero, then the result is -(2<sup>28</sup>).
* </ul>
*
* @param d floating-point number whose exponent is to be extracted
* @return unbiased exponent of the argument.
* @author Joseph D. Darcy
*/
public static int ilogb(double d) {
int exponent = getExponent(d);
switch (exponent) {
case DoubleConsts.MAX_EXPONENT+1: // NaN or infinity
if( isNaN(d) )
return (1<<30); // 2^30
else // infinite value
return (1<<28); // 2^28
case DoubleConsts.MIN_EXPONENT-1: // zero or subnormal
if(d == 0.0) {
return -(1<<28); // -(2^28)
}
else {
long transducer = Double.doubleToRawLongBits(d);
/*
* To avoid causing slow arithmetic on subnormals,
* the scaling to determine when d's significand
* is normalized is done in integer arithmetic.
* (there must be at least one "1" bit in the
* significand since zero has been screened out.
*/
// isolate significand bits
transducer &= DoubleConsts.SIGNIF_BIT_MASK;
assert(transducer != 0L);
// This loop is simple and functional. We might be
// able to do something more clever that was faster;
// e.g. number of leading zero detection on
// (transducer << (# exponent and sign bits).
while (transducer <
(1L << (DoubleConsts.SIGNIFICAND_WIDTH - 1))) {
transducer *= 2;
exponent--;
}
exponent++;
assert( exponent >=
DoubleConsts.MIN_EXPONENT - (DoubleConsts.SIGNIFICAND_WIDTH-1) &&
exponent < DoubleConsts.MIN_EXPONENT);
return exponent;
}
default:
assert( exponent >= DoubleConsts.MIN_EXPONENT &&
exponent <= DoubleConsts.MAX_EXPONENT);
return exponent;
}
}
Example 7
| Source File: FpUtils.java From javaide with GNU General Public License v3.0 | 4 votes |
|
/**
* Returns unbiased exponent of a <code>double</code>; for
* subnormal values, the number is treated as if it were
* normalized. That is for all finite, non-zero, positive numbers
* <i>x</i>, <code>scalb(<i>x</i>, -ilogb(<i>x</i>))</code> is
* always in the range [1, 2).
* <p>
* Special cases:
* <ul>
* <li> If the argument is NaN, then the result is 2<sup>30</sup>.
* <li> If the argument is infinite, then the result is 2<sup>28</sup>.
* <li> If the argument is zero, then the result is -(2<sup>28</sup>).
* </ul>
*
* @param d floating-point number whose exponent is to be extracted
* @return unbiased exponent of the argument.
* @author Joseph D. Darcy
*/
public static int ilogb(double d) {
int exponent = getExponent(d);
switch (exponent) {
case DoubleConsts.MAX_EXPONENT+1: // NaN or infinity
if( isNaN(d) )
return (1<<30); // 2^30
else // infinite value
return (1<<28); // 2^28
// break;
case DoubleConsts.MIN_EXPONENT-1: // zero or subnormal
if(d == 0.0) {
return -(1<<28); // -(2^28)
}
else {
long transducer = Double.doubleToRawLongBits(d);
/*
* To avoid causing slow arithmetic on subnormals,
* the scaling to determine when d's significand
* is normalized is done in integer arithmetic.
* (there must be at least one "1" bit in the
* significand since zero has been screened out.
*/
// isolate significand bits
transducer &= DoubleConsts.SIGNIF_BIT_MASK;
assert(transducer != 0L);
// This loop is simple and functional. We might be
// able to do something more clever that was faster;
// e.g. number of leading zero detection on
// (transducer << (# exponent and sign bits).
while (transducer <
(1L << (DoubleConsts.SIGNIFICAND_WIDTH - 1))) {
transducer *= 2;
exponent--;
}
exponent++;
assert( exponent >=
DoubleConsts.MIN_EXPONENT - (DoubleConsts.SIGNIFICAND_WIDTH-1) &&
exponent < DoubleConsts.MIN_EXPONENT);
return exponent;
}
// break;
default:
assert( exponent >= DoubleConsts.MIN_EXPONENT &&
exponent <= DoubleConsts.MAX_EXPONENT);
return exponent;
// break;
}
}
Example 8
| Source File: FpUtils.java From jdk8u-jdk with GNU General Public License v2.0 | 4 votes |
|
/**
* Returns unbiased exponent of a {@code double}; for
* subnormal values, the number is treated as if it were
* normalized. That is for all finite, non-zero, positive numbers
* <i>x</i>, <code>scalb(<i>x</i>, -ilogb(<i>x</i>))</code> is
* always in the range [1, 2).
* <p>
* Special cases:
* <ul>
* <li> If the argument is NaN, then the result is 2<sup>30</sup>.
* <li> If the argument is infinite, then the result is 2<sup>28</sup>.
* <li> If the argument is zero, then the result is -(2<sup>28</sup>).
* </ul>
*
* @param d floating-point number whose exponent is to be extracted
* @return unbiased exponent of the argument.
* @author Joseph D. Darcy
*/
public static int ilogb(double d) {
int exponent = getExponent(d);
switch (exponent) {
case DoubleConsts.MAX_EXPONENT+1: // NaN or infinity
if( isNaN(d) )
return (1<<30); // 2^30
else // infinite value
return (1<<28); // 2^28
case DoubleConsts.MIN_EXPONENT-1: // zero or subnormal
if(d == 0.0) {
return -(1<<28); // -(2^28)
}
else {
long transducer = Double.doubleToRawLongBits(d);
/*
* To avoid causing slow arithmetic on subnormals,
* the scaling to determine when d's significand
* is normalized is done in integer arithmetic.
* (there must be at least one "1" bit in the
* significand since zero has been screened out.
*/
// isolate significand bits
transducer &= DoubleConsts.SIGNIF_BIT_MASK;
assert(transducer != 0L);
// This loop is simple and functional. We might be
// able to do something more clever that was faster;
// e.g. number of leading zero detection on
// (transducer << (# exponent and sign bits).
while (transducer <
(1L << (DoubleConsts.SIGNIFICAND_WIDTH - 1))) {
transducer *= 2;
exponent--;
}
exponent++;
assert( exponent >=
DoubleConsts.MIN_EXPONENT - (DoubleConsts.SIGNIFICAND_WIDTH-1) &&
exponent < DoubleConsts.MIN_EXPONENT);
return exponent;
}
default:
assert( exponent >= DoubleConsts.MIN_EXPONENT &&
exponent <= DoubleConsts.MAX_EXPONENT);
return exponent;
}
}
Example 9
| Source File: FpUtils.java From hottub with GNU General Public License v2.0 | 4 votes |
|
/**
* Returns unbiased exponent of a {@code double}; for
* subnormal values, the number is treated as if it were
* normalized. That is for all finite, non-zero, positive numbers
* <i>x</i>, <code>scalb(<i>x</i>, -ilogb(<i>x</i>))</code> is
* always in the range [1, 2).
* <p>
* Special cases:
* <ul>
* <li> If the argument is NaN, then the result is 2<sup>30</sup>.
* <li> If the argument is infinite, then the result is 2<sup>28</sup>.
* <li> If the argument is zero, then the result is -(2<sup>28</sup>).
* </ul>
*
* @param d floating-point number whose exponent is to be extracted
* @return unbiased exponent of the argument.
* @author Joseph D. Darcy
*/
public static int ilogb(double d) {
int exponent = getExponent(d);
switch (exponent) {
case DoubleConsts.MAX_EXPONENT+1: // NaN or infinity
if( isNaN(d) )
return (1<<30); // 2^30
else // infinite value
return (1<<28); // 2^28
case DoubleConsts.MIN_EXPONENT-1: // zero or subnormal
if(d == 0.0) {
return -(1<<28); // -(2^28)
}
else {
long transducer = Double.doubleToRawLongBits(d);
/*
* To avoid causing slow arithmetic on subnormals,
* the scaling to determine when d's significand
* is normalized is done in integer arithmetic.
* (there must be at least one "1" bit in the
* significand since zero has been screened out.
*/
// isolate significand bits
transducer &= DoubleConsts.SIGNIF_BIT_MASK;
assert(transducer != 0L);
// This loop is simple and functional. We might be
// able to do something more clever that was faster;
// e.g. number of leading zero detection on
// (transducer << (# exponent and sign bits).
while (transducer <
(1L << (DoubleConsts.SIGNIFICAND_WIDTH - 1))) {
transducer *= 2;
exponent--;
}
exponent++;
assert( exponent >=
DoubleConsts.MIN_EXPONENT - (DoubleConsts.SIGNIFICAND_WIDTH-1) &&
exponent < DoubleConsts.MIN_EXPONENT);
return exponent;
}
default:
assert( exponent >= DoubleConsts.MIN_EXPONENT &&
exponent <= DoubleConsts.MAX_EXPONENT);
return exponent;
}
}
Example 10
| Source File: FpUtils.java From openjdk-8-source with GNU General Public License v2.0 | 4 votes |
|
/**
* Returns unbiased exponent of a {@code double}; for
* subnormal values, the number is treated as if it were
* normalized. That is for all finite, non-zero, positive numbers
* <i>x</i>, <code>scalb(<i>x</i>, -ilogb(<i>x</i>))</code> is
* always in the range [1, 2).
* <p>
* Special cases:
* <ul>
* <li> If the argument is NaN, then the result is 2<sup>30</sup>.
* <li> If the argument is infinite, then the result is 2<sup>28</sup>.
* <li> If the argument is zero, then the result is -(2<sup>28</sup>).
* </ul>
*
* @param d floating-point number whose exponent is to be extracted
* @return unbiased exponent of the argument.
* @author Joseph D. Darcy
*/
public static int ilogb(double d) {
int exponent = getExponent(d);
switch (exponent) {
case DoubleConsts.MAX_EXPONENT+1: // NaN or infinity
if( isNaN(d) )
return (1<<30); // 2^30
else // infinite value
return (1<<28); // 2^28
case DoubleConsts.MIN_EXPONENT-1: // zero or subnormal
if(d == 0.0) {
return -(1<<28); // -(2^28)
}
else {
long transducer = Double.doubleToRawLongBits(d);
/*
* To avoid causing slow arithmetic on subnormals,
* the scaling to determine when d's significand
* is normalized is done in integer arithmetic.
* (there must be at least one "1" bit in the
* significand since zero has been screened out.
*/
// isolate significand bits
transducer &= DoubleConsts.SIGNIF_BIT_MASK;
assert(transducer != 0L);
// This loop is simple and functional. We might be
// able to do something more clever that was faster;
// e.g. number of leading zero detection on
// (transducer << (# exponent and sign bits).
while (transducer <
(1L << (DoubleConsts.SIGNIFICAND_WIDTH - 1))) {
transducer *= 2;
exponent--;
}
exponent++;
assert( exponent >=
DoubleConsts.MIN_EXPONENT - (DoubleConsts.SIGNIFICAND_WIDTH-1) &&
exponent < DoubleConsts.MIN_EXPONENT);
return exponent;
}
default:
assert( exponent >= DoubleConsts.MIN_EXPONENT &&
exponent <= DoubleConsts.MAX_EXPONENT);
return exponent;
}
}
Example 11
| Source File: FpUtils.java From openjdk-8 with GNU General Public License v2.0 | 4 votes |
|
/**
* Returns unbiased exponent of a {@code double}; for
* subnormal values, the number is treated as if it were
* normalized. That is for all finite, non-zero, positive numbers
* <i>x</i>, <code>scalb(<i>x</i>, -ilogb(<i>x</i>))</code> is
* always in the range [1, 2).
* <p>
* Special cases:
* <ul>
* <li> If the argument is NaN, then the result is 2<sup>30</sup>.
* <li> If the argument is infinite, then the result is 2<sup>28</sup>.
* <li> If the argument is zero, then the result is -(2<sup>28</sup>).
* </ul>
*
* @param d floating-point number whose exponent is to be extracted
* @return unbiased exponent of the argument.
* @author Joseph D. Darcy
*/
public static int ilogb(double d) {
int exponent = getExponent(d);
switch (exponent) {
case DoubleConsts.MAX_EXPONENT+1: // NaN or infinity
if( isNaN(d) )
return (1<<30); // 2^30
else // infinite value
return (1<<28); // 2^28
case DoubleConsts.MIN_EXPONENT-1: // zero or subnormal
if(d == 0.0) {
return -(1<<28); // -(2^28)
}
else {
long transducer = Double.doubleToRawLongBits(d);
/*
* To avoid causing slow arithmetic on subnormals,
* the scaling to determine when d's significand
* is normalized is done in integer arithmetic.
* (there must be at least one "1" bit in the
* significand since zero has been screened out.
*/
// isolate significand bits
transducer &= DoubleConsts.SIGNIF_BIT_MASK;
assert(transducer != 0L);
// This loop is simple and functional. We might be
// able to do something more clever that was faster;
// e.g. number of leading zero detection on
// (transducer << (# exponent and sign bits).
while (transducer <
(1L << (DoubleConsts.SIGNIFICAND_WIDTH - 1))) {
transducer *= 2;
exponent--;
}
exponent++;
assert( exponent >=
DoubleConsts.MIN_EXPONENT - (DoubleConsts.SIGNIFICAND_WIDTH-1) &&
exponent < DoubleConsts.MIN_EXPONENT);
return exponent;
}
default:
assert( exponent >= DoubleConsts.MIN_EXPONENT &&
exponent <= DoubleConsts.MAX_EXPONENT);
return exponent;
}
}
Example 12
| Source File: FpUtils.java From jdk8u_jdk with GNU General Public License v2.0 | 4 votes |
|
/**
* Returns unbiased exponent of a {@code double}; for
* subnormal values, the number is treated as if it were
* normalized. That is for all finite, non-zero, positive numbers
* <i>x</i>, <code>scalb(<i>x</i>, -ilogb(<i>x</i>))</code> is
* always in the range [1, 2).
* <p>
* Special cases:
* <ul>
* <li> If the argument is NaN, then the result is 2<sup>30</sup>.
* <li> If the argument is infinite, then the result is 2<sup>28</sup>.
* <li> If the argument is zero, then the result is -(2<sup>28</sup>).
* </ul>
*
* @param d floating-point number whose exponent is to be extracted
* @return unbiased exponent of the argument.
* @author Joseph D. Darcy
*/
public static int ilogb(double d) {
int exponent = getExponent(d);
switch (exponent) {
case DoubleConsts.MAX_EXPONENT+1: // NaN or infinity
if( isNaN(d) )
return (1<<30); // 2^30
else // infinite value
return (1<<28); // 2^28
case DoubleConsts.MIN_EXPONENT-1: // zero or subnormal
if(d == 0.0) {
return -(1<<28); // -(2^28)
}
else {
long transducer = Double.doubleToRawLongBits(d);
/*
* To avoid causing slow arithmetic on subnormals,
* the scaling to determine when d's significand
* is normalized is done in integer arithmetic.
* (there must be at least one "1" bit in the
* significand since zero has been screened out.
*/
// isolate significand bits
transducer &= DoubleConsts.SIGNIF_BIT_MASK;
assert(transducer != 0L);
// This loop is simple and functional. We might be
// able to do something more clever that was faster;
// e.g. number of leading zero detection on
// (transducer << (# exponent and sign bits).
while (transducer <
(1L << (DoubleConsts.SIGNIFICAND_WIDTH - 1))) {
transducer *= 2;
exponent--;
}
exponent++;
assert( exponent >=
DoubleConsts.MIN_EXPONENT - (DoubleConsts.SIGNIFICAND_WIDTH-1) &&
exponent < DoubleConsts.MIN_EXPONENT);
return exponent;
}
default:
assert( exponent >= DoubleConsts.MIN_EXPONENT &&
exponent <= DoubleConsts.MAX_EXPONENT);
return exponent;
}
}
Example 13
| Source File: FpUtils.java From jdk8u-jdk with GNU General Public License v2.0 | 4 votes |
|
/**
* Returns unbiased exponent of a {@code double}; for
* subnormal values, the number is treated as if it were
* normalized. That is for all finite, non-zero, positive numbers
* <i>x</i>, <code>scalb(<i>x</i>, -ilogb(<i>x</i>))</code> is
* always in the range [1, 2).
* <p>
* Special cases:
* <ul>
* <li> If the argument is NaN, then the result is 2<sup>30</sup>.
* <li> If the argument is infinite, then the result is 2<sup>28</sup>.
* <li> If the argument is zero, then the result is -(2<sup>28</sup>).
* </ul>
*
* @param d floating-point number whose exponent is to be extracted
* @return unbiased exponent of the argument.
* @author Joseph D. Darcy
*/
public static int ilogb(double d) {
int exponent = getExponent(d);
switch (exponent) {
case DoubleConsts.MAX_EXPONENT+1: // NaN or infinity
if( isNaN(d) )
return (1<<30); // 2^30
else // infinite value
return (1<<28); // 2^28
case DoubleConsts.MIN_EXPONENT-1: // zero or subnormal
if(d == 0.0) {
return -(1<<28); // -(2^28)
}
else {
long transducer = Double.doubleToRawLongBits(d);
/*
* To avoid causing slow arithmetic on subnormals,
* the scaling to determine when d's significand
* is normalized is done in integer arithmetic.
* (there must be at least one "1" bit in the
* significand since zero has been screened out.
*/
// isolate significand bits
transducer &= DoubleConsts.SIGNIF_BIT_MASK;
assert(transducer != 0L);
// This loop is simple and functional. We might be
// able to do something more clever that was faster;
// e.g. number of leading zero detection on
// (transducer << (# exponent and sign bits).
while (transducer <
(1L << (DoubleConsts.SIGNIFICAND_WIDTH - 1))) {
transducer *= 2;
exponent--;
}
exponent++;
assert( exponent >=
DoubleConsts.MIN_EXPONENT - (DoubleConsts.SIGNIFICAND_WIDTH-1) &&
exponent < DoubleConsts.MIN_EXPONENT);
return exponent;
}
default:
assert( exponent >= DoubleConsts.MIN_EXPONENT &&
exponent <= DoubleConsts.MAX_EXPONENT);
return exponent;
}
}
Example 14
| Source File: FpUtils.java From jdk8u-dev-jdk with GNU General Public License v2.0 | 4 votes |
|
/**
* Returns unbiased exponent of a {@code double}; for
* subnormal values, the number is treated as if it were
* normalized. That is for all finite, non-zero, positive numbers
* <i>x</i>, <code>scalb(<i>x</i>, -ilogb(<i>x</i>))</code> is
* always in the range [1, 2).
* <p>
* Special cases:
* <ul>
* <li> If the argument is NaN, then the result is 2<sup>30</sup>.
* <li> If the argument is infinite, then the result is 2<sup>28</sup>.
* <li> If the argument is zero, then the result is -(2<sup>28</sup>).
* </ul>
*
* @param d floating-point number whose exponent is to be extracted
* @return unbiased exponent of the argument.
* @author Joseph D. Darcy
*/
public static int ilogb(double d) {
int exponent = getExponent(d);
switch (exponent) {
case DoubleConsts.MAX_EXPONENT+1: // NaN or infinity
if( isNaN(d) )
return (1<<30); // 2^30
else // infinite value
return (1<<28); // 2^28
case DoubleConsts.MIN_EXPONENT-1: // zero or subnormal
if(d == 0.0) {
return -(1<<28); // -(2^28)
}
else {
long transducer = Double.doubleToRawLongBits(d);
/*
* To avoid causing slow arithmetic on subnormals,
* the scaling to determine when d's significand
* is normalized is done in integer arithmetic.
* (there must be at least one "1" bit in the
* significand since zero has been screened out.
*/
// isolate significand bits
transducer &= DoubleConsts.SIGNIF_BIT_MASK;
assert(transducer != 0L);
// This loop is simple and functional. We might be
// able to do something more clever that was faster;
// e.g. number of leading zero detection on
// (transducer << (# exponent and sign bits).
while (transducer <
(1L << (DoubleConsts.SIGNIFICAND_WIDTH - 1))) {
transducer *= 2;
exponent--;
}
exponent++;
assert( exponent >=
DoubleConsts.MIN_EXPONENT - (DoubleConsts.SIGNIFICAND_WIDTH-1) &&
exponent < DoubleConsts.MIN_EXPONENT);
return exponent;
}
default:
assert( exponent >= DoubleConsts.MIN_EXPONENT &&
exponent <= DoubleConsts.MAX_EXPONENT);
return exponent;
}
}
Example 15
| Source File: FpUtils.java From j2objc with Apache License 2.0 | 4 votes |
|
/**
* Returns unbiased exponent of a {@code double}; for
* subnormal values, the number is treated as if it were
* normalized. That is for all finite, non-zero, positive numbers
* <i>x</i>, <code>scalb(<i>x</i>, -ilogb(<i>x</i>))</code> is
* always in the range [1, 2).
* <p>
* Special cases:
* <ul>
* <li> If the argument is NaN, then the result is 2<sup>30</sup>.
* <li> If the argument is infinite, then the result is 2<sup>28</sup>.
* <li> If the argument is zero, then the result is -(2<sup>28</sup>).
* </ul>
*
* @param d floating-point number whose exponent is to be extracted
* @return unbiased exponent of the argument.
* @author Joseph D. Darcy
*/
public static int ilogb(double d) {
int exponent = getExponent(d);
switch (exponent) {
case DoubleConsts.MAX_EXPONENT+1: // NaN or infinity
if( isNaN(d) )
return (1<<30); // 2^30
else // infinite value
return (1<<28); // 2^28
case DoubleConsts.MIN_EXPONENT-1: // zero or subnormal
if(d == 0.0) {
return -(1<<28); // -(2^28)
}
else {
long transducer = Double.doubleToRawLongBits(d);
/*
* To avoid causing slow arithmetic on subnormals,
* the scaling to determine when d's significand
* is normalized is done in integer arithmetic.
* (there must be at least one "1" bit in the
* significand since zero has been screened out.
*/
// isolate significand bits
transducer &= DoubleConsts.SIGNIF_BIT_MASK;
assert(transducer != 0L);
// This loop is simple and functional. We might be
// able to do something more clever that was faster;
// e.g. number of leading zero detection on
// (transducer << (# exponent and sign bits).
while (transducer <
(1L << (DoubleConsts.SIGNIFICAND_WIDTH - 1))) {
transducer *= 2;
exponent--;
}
exponent++;
assert( exponent >=
DoubleConsts.MIN_EXPONENT - (DoubleConsts.SIGNIFICAND_WIDTH-1) &&
exponent < DoubleConsts.MIN_EXPONENT);
return exponent;
}
default:
assert( exponent >= DoubleConsts.MIN_EXPONENT &&
exponent <= DoubleConsts.MAX_EXPONENT);
return exponent;
}
}
