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A library jar that provides APIs for Applications written for the Google Android Platform.
/*
* Copyright (C) 2016 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package android.util;
import android.annotation.HalfFloat;
import android.annotation.NonNull;
import android.annotation.Nullable;
import libcore.util.FP16;
/**
* The {@code Half} class is a wrapper and a utility class to manipulate half-precision 16-bit
* IEEE 754
* floating point data types (also called fp16 or binary16). A half-precision float can be
* created from or converted to single-precision floats, and is stored in a short data type.
* To distinguish short values holding half-precision floats from regular short values,
* it is recommended to use the @HalfFloat annotation.
*
* The IEEE 754 standard specifies an fp16 as having the following format:
*
* - Sign bit: 1 bit
* - Exponent width: 5 bits
* - Significand: 10 bits
*
*
* The format is laid out as follows:
*
* 1 11111 1111111111
* ^ --^-- -----^----
* sign | |_______ significand
* |
* -- exponent
*
*
* Half-precision floating points can be useful to save memory and/or
* bandwidth at the expense of range and precision when compared to single-precision
* floating points (fp32).
* To help you decide whether fp16 is the right storage type for you need, please
* refer to the table below that shows the available precision throughout the range of
* possible values. The precision column indicates the step size between two
* consecutive numbers in a specific part of the range.
*
*
* Range start Precision 0 1 ⁄ 16,777,216 1 ⁄ 16,384 1 ⁄ 16,777,216 1 ⁄ 8,192 1 ⁄ 8,388,608 1 ⁄ 4,096 1 ⁄ 4,194,304 1 ⁄ 2,048 1 ⁄ 2,097,152 1 ⁄ 1,024 1 ⁄ 1,048,576 1 ⁄ 512 1 ⁄ 524,288 1 ⁄ 256 1 ⁄ 262,144 1 ⁄ 128 1 ⁄ 131,072 1 ⁄ 64 1 ⁄ 65,536 1 ⁄ 32 1 ⁄ 32,768 1 ⁄ 16 1 ⁄ 16,384 1 ⁄ 8 1 ⁄ 8,192 1 ⁄ 4 1 ⁄ 4,096 1 ⁄ 2 1 ⁄ 2,048 1 1 ⁄ 1,024 2 1 ⁄ 512 4 1 ⁄ 256 8 1 ⁄ 128 16 1 ⁄ 64 32 1 ⁄ 32 64 1 ⁄ 16 128 1 ⁄ 8 256 1 ⁄ 4 512 1 ⁄ 2 1,024 1 2,048 2 4,096 4 8,192 8 16,384 16 32,768 32
*
* This table shows that numbers higher than 1024 lose all fractional precision.
*/
@SuppressWarnings("SimplifiableIfStatement")
public final class Half extends Number implements Comparable {
/**
* The number of bits used to represent a half-precision float value.
*/
public static final int SIZE = 16;
/**
* Epsilon is the difference between 1.0 and the next value representable
* by a half-precision floating-point.
*/
public static final @HalfFloat short EPSILON = (short) 0x1400;
/**
* Maximum exponent a finite half-precision float may have.
*/
public static final int MAX_EXPONENT = 15;
/**
* Minimum exponent a normalized half-precision float may have.
*/
public static final int MIN_EXPONENT = -14;
/**
* Smallest negative value a half-precision float may have.
*/
public static final @HalfFloat short LOWEST_VALUE = (short) 0xfbff;
/**
* Maximum positive finite value a half-precision float may have.
*/
public static final @HalfFloat short MAX_VALUE = (short) 0x7bff;
/**
* Smallest positive normal value a half-precision float may have.
*/
public static final @HalfFloat short MIN_NORMAL = (short) 0x0400;
/**
* Smallest positive non-zero value a half-precision float may have.
*/
public static final @HalfFloat short MIN_VALUE = (short) 0x0001;
/**
* A Not-a-Number representation of a half-precision float.
*/
public static final @HalfFloat short NaN = (short) 0x7e00;
/**
* Negative infinity of type half-precision float.
*/
public static final @HalfFloat short NEGATIVE_INFINITY = (short) 0xfc00;
/**
* Negative 0 of type half-precision float.
*/
public static final @HalfFloat short NEGATIVE_ZERO = (short) 0x8000;
/**
* Positive infinity of type half-precision float.
*/
public static final @HalfFloat short POSITIVE_INFINITY = (short) 0x7c00;
/**
* Positive 0 of type half-precision float.
*/
public static final @HalfFloat short POSITIVE_ZERO = (short) 0x0000;
private final @HalfFloat short mValue;
/**
* Constructs a newly allocated {@code Half} object that represents the
* half-precision float type argument.
*
* @param value The value to be represented by the {@code Half}
*/
public Half(@HalfFloat short value) {
mValue = value;
}
/**
* Constructs a newly allocated {@code Half} object that represents the
* argument converted to a half-precision float.
*
* @param value The value to be represented by the {@code Half}
*
* @see #toHalf(float)
*/
public Half(float value) {
mValue = toHalf(value);
}
/**
* Constructs a newly allocated {@code Half} object that
* represents the argument converted to a half-precision float.
*
* @param value The value to be represented by the {@code Half}
*
* @see #toHalf(float)
*/
public Half(double value) {
mValue = toHalf((float) value);
}
/**
* Constructs a newly allocated {@code Half} object that represents the
* half-precision float value represented by the string.
* The string is converted to a half-precision float value as if by the
* {@link #valueOf(String)} method.
*
* Calling this constructor is equivalent to calling:
*
* new Half(Float.parseFloat(value))
*
*
* @param value A string to be converted to a {@code Half}
* @throws NumberFormatException if the string does not contain a parsable number
*
* @see Float#valueOf(java.lang.String)
* @see #toHalf(float)
*/
public Half(@NonNull String value) throws NumberFormatException {
mValue = toHalf(Float.parseFloat(value));
}
/**
* Returns the half-precision value of this {@code Half} as a {@code short}
* containing the bit representation described in {@link Half}.
*
* @return The half-precision float value represented by this object
*/
public @HalfFloat short halfValue() {
return mValue;
}
/**
* Returns the value of this {@code Half} as a {@code byte} after
* a narrowing primitive conversion.
*
* @return The half-precision float value represented by this object
* converted to type {@code byte}
*/
@Override
public byte byteValue() {
return (byte) toFloat(mValue);
}
/**
* Returns the value of this {@code Half} as a {@code short} after
* a narrowing primitive conversion.
*
* @return The half-precision float value represented by this object
* converted to type {@code short}
*/
@Override
public short shortValue() {
return (short) toFloat(mValue);
}
/**
* Returns the value of this {@code Half} as a {@code int} after
* a narrowing primitive conversion.
*
* @return The half-precision float value represented by this object
* converted to type {@code int}
*/
@Override
public int intValue() {
return (int) toFloat(mValue);
}
/**
* Returns the value of this {@code Half} as a {@code long} after
* a narrowing primitive conversion.
*
* @return The half-precision float value represented by this object
* converted to type {@code long}
*/
@Override
public long longValue() {
return (long) toFloat(mValue);
}
/**
* Returns the value of this {@code Half} as a {@code float} after
* a widening primitive conversion.
*
* @return The half-precision float value represented by this object
* converted to type {@code float}
*/
@Override
public float floatValue() {
return toFloat(mValue);
}
/**
* Returns the value of this {@code Half} as a {@code double} after
* a widening primitive conversion.
*
* @return The half-precision float value represented by this object
* converted to type {@code double}
*/
@Override
public double doubleValue() {
return toFloat(mValue);
}
/**
* Returns true if this {@code Half} value represents a Not-a-Number,
* false otherwise.
*
* @return True if the value is a NaN, false otherwise
*/
public boolean isNaN() {
return isNaN(mValue);
}
/**
* Compares this object against the specified object. The result is {@code true}
* if and only if the argument is not {@code null} and is a {@code Half} object
* that represents the same half-precision value as the this object. Two
* half-precision values are considered to be the same if and only if the method
* {@link #halfToIntBits(short)} returns an identical {@code int} value for both.
*
* @param o The object to compare
* @return True if the objects are the same, false otherwise
*
* @see #halfToIntBits(short)
*/
@Override
public boolean equals(@Nullable Object o) {
return (o instanceof Half) &&
(halfToIntBits(((Half) o).mValue) == halfToIntBits(mValue));
}
/**
* Returns a hash code for this {@code Half} object. The result is the
* integer bit representation, exactly as produced by the method
* {@link #halfToIntBits(short)}, of the primitive half-precision float
* value represented by this {@code Half} object.
*
* @return A hash code value for this object
*/
@Override
public int hashCode() {
return hashCode(mValue);
}
/**
* Returns a string representation of the specified half-precision
* float value. See {@link #toString(short)} for more information.
*
* @return A string representation of this {@code Half} object
*/
@NonNull
@Override
public String toString() {
return toString(mValue);
}
/**
* Compares the two specified half-precision float values. The following
* conditions apply during the comparison:
*
*
* - {@link #NaN} is considered by this method to be equal to itself and greater
* than all other half-precision float values (including {@code #POSITIVE_INFINITY})
* - {@link #POSITIVE_ZERO} is considered by this method to be greater than
* {@link #NEGATIVE_ZERO}.
*
*
* @param h The half-precision float value to compare to the half-precision value
* represented by this {@code Half} object
*
* @return The value {@code 0} if {@code x} is numerically equal to {@code y}; a
* value less than {@code 0} if {@code x} is numerically less than {@code y};
* and a value greater than {@code 0} if {@code x} is numerically greater
* than {@code y}
*/
@Override
public int compareTo(@NonNull Half h) {
return compare(mValue, h.mValue);
}
/**
* Returns a hash code for a half-precision float value.
*
* @param h The value to hash
*
* @return A hash code value for a half-precision float value
*/
public static int hashCode(@HalfFloat short h) {
return halfToIntBits(h);
}
/**
* Compares the two specified half-precision float values. The following
* conditions apply during the comparison:
*
*
* - {@link #NaN} is considered by this method to be equal to itself and greater
* than all other half-precision float values (including {@code #POSITIVE_INFINITY})
* - {@link #POSITIVE_ZERO} is considered by this method to be greater than
* {@link #NEGATIVE_ZERO}.
*
*
* @param x The first half-precision float value to compare.
* @param y The second half-precision float value to compare
*
* @return The value {@code 0} if {@code x} is numerically equal to {@code y}, a
* value less than {@code 0} if {@code x} is numerically less than {@code y},
* and a value greater than {@code 0} if {@code x} is numerically greater
* than {@code y}
*/
public static int compare(@HalfFloat short x, @HalfFloat short y) {
return FP16.compare(x, y);
}
/**
* Returns a representation of the specified half-precision float value
* according to the bit layout described in {@link Half}.
*
* Similar to {@link #halfToIntBits(short)}, this method collapses all
* possible Not-a-Number values to a single canonical Not-a-Number value
* defined by {@link #NaN}.
*
* @param h A half-precision float value
* @return The bits that represent the half-precision float value
*
* @see #halfToIntBits(short)
*/
public static @HalfFloat short halfToShortBits(@HalfFloat short h) {
return (h & FP16.EXPONENT_SIGNIFICAND_MASK) > FP16.POSITIVE_INFINITY ? NaN : h;
}
/**
* Returns a representation of the specified half-precision float value
* according to the bit layout described in {@link Half}.
*
* Unlike {@link #halfToRawIntBits(short)}, this method collapses all
* possible Not-a-Number values to a single canonical Not-a-Number value
* defined by {@link #NaN}.
*
* @param h A half-precision float value
* @return The bits that represent the half-precision float value
*
* @see #halfToRawIntBits(short)
* @see #halfToShortBits(short)
* @see #intBitsToHalf(int)
*/
public static int halfToIntBits(@HalfFloat short h) {
return (h & FP16.EXPONENT_SIGNIFICAND_MASK) > FP16.POSITIVE_INFINITY ? NaN : h & 0xffff;
}
/**
* Returns a representation of the specified half-precision float value
* according to the bit layout described in {@link Half}.
*
* The argument is considered to be a representation of a half-precision
* float value according to the bit layout described in {@link Half}. The 16
* most significant bits of the returned value are set to 0.
*
* @param h A half-precision float value
* @return The bits that represent the half-precision float value
*
* @see #halfToIntBits(short)
* @see #intBitsToHalf(int)
*/
public static int halfToRawIntBits(@HalfFloat short h) {
return h & 0xffff;
}
/**
* Returns the half-precision float value corresponding to a given
* bit representation.
*
* The argument is considered to be a representation of a half-precision
* float value according to the bit layout described in {@link Half}. The 16
* most significant bits of the argument are ignored.
*
* @param bits An integer
* @return The half-precision float value with the same bit pattern
*/
public static @HalfFloat short intBitsToHalf(int bits) {
return (short) (bits & 0xffff);
}
/**
* Returns the first parameter with the sign of the second parameter.
* This method treats NaNs as having a sign.
*
* @param magnitude A half-precision float value providing the magnitude of the result
* @param sign A half-precision float value providing the sign of the result
* @return A value with the magnitude of the first parameter and the sign
* of the second parameter
*/
public static @HalfFloat short copySign(@HalfFloat short magnitude, @HalfFloat short sign) {
return (short) ((sign & FP16.SIGN_MASK) | (magnitude & FP16.EXPONENT_SIGNIFICAND_MASK));
}
/**
* Returns the absolute value of the specified half-precision float.
* Special values are handled in the following ways:
*
* - If the specified half-precision float is NaN, the result is NaN
* - If the specified half-precision float is zero (negative or positive),
* the result is positive zero (see {@link #POSITIVE_ZERO})
* - If the specified half-precision float is infinity (negative or positive),
* the result is positive infinity (see {@link #POSITIVE_INFINITY})
*
*
* @param h A half-precision float value
* @return The absolute value of the specified half-precision float
*/
public static @HalfFloat short abs(@HalfFloat short h) {
return (short) (h & FP16.EXPONENT_SIGNIFICAND_MASK);
}
/**
* Returns the closest integral half-precision float value to the specified
* half-precision float value. Special values are handled in the
* following ways:
*
* - If the specified half-precision float is NaN, the result is NaN
* - If the specified half-precision float is infinity (negative or positive),
* the result is infinity (with the same sign)
* - If the specified half-precision float is zero (negative or positive),
* the result is zero (with the same sign)
*
*
*
* Note: Unlike the identically named
* int java.lang.Math.round(float) method,
* this returns a Half value stored in a short, not an
* actual short integer result.
*
* @param h A half-precision float value
* @return The value of the specified half-precision float rounded to the nearest
* half-precision float value
*/
public static @HalfFloat short round(@HalfFloat short h) {
return FP16.rint(h);
}
/**
* Returns the smallest half-precision float value toward negative infinity
* greater than or equal to the specified half-precision float value.
* Special values are handled in the following ways:
*
* - If the specified half-precision float is NaN, the result is NaN
* - If the specified half-precision float is infinity (negative or positive),
* the result is infinity (with the same sign)
* - If the specified half-precision float is zero (negative or positive),
* the result is zero (with the same sign)
*
*
* @param h A half-precision float value
* @return The smallest half-precision float value toward negative infinity
* greater than or equal to the specified half-precision float value
*/
public static @HalfFloat short ceil(@HalfFloat short h) {
return FP16.ceil(h);
}
/**
* Returns the largest half-precision float value toward positive infinity
* less than or equal to the specified half-precision float value.
* Special values are handled in the following ways:
*
* - If the specified half-precision float is NaN, the result is NaN
* - If the specified half-precision float is infinity (negative or positive),
* the result is infinity (with the same sign)
* - If the specified half-precision float is zero (negative or positive),
* the result is zero (with the same sign)
*
*
* @param h A half-precision float value
* @return The largest half-precision float value toward positive infinity
* less than or equal to the specified half-precision float value
*/
public static @HalfFloat short floor(@HalfFloat short h) {
return FP16.floor(h);
}
/**
* Returns the truncated half-precision float value of the specified
* half-precision float value. Special values are handled in the following ways:
*
* - If the specified half-precision float is NaN, the result is NaN
* - If the specified half-precision float is infinity (negative or positive),
* the result is infinity (with the same sign)
* - If the specified half-precision float is zero (negative or positive),
* the result is zero (with the same sign)
*
*
* @param h A half-precision float value
* @return The truncated half-precision float value of the specified
* half-precision float value
*/
public static @HalfFloat short trunc(@HalfFloat short h) {
return FP16.trunc(h);
}
/**
* Returns the smaller of two half-precision float values (the value closest
* to negative infinity). Special values are handled in the following ways:
*
* - If either value is NaN, the result is NaN
* - {@link #NEGATIVE_ZERO} is smaller than {@link #POSITIVE_ZERO}
*
*
* @param x The first half-precision value
* @param y The second half-precision value
* @return The smaller of the two specified half-precision values
*/
public static @HalfFloat short min(@HalfFloat short x, @HalfFloat short y) {
return FP16.min(x, y);
}
/**
* Returns the larger of two half-precision float values (the value closest
* to positive infinity). Special values are handled in the following ways:
*
* - If either value is NaN, the result is NaN
* - {@link #POSITIVE_ZERO} is greater than {@link #NEGATIVE_ZERO}
*
*
* @param x The first half-precision value
* @param y The second half-precision value
*
* @return The larger of the two specified half-precision values
*/
public static @HalfFloat short max(@HalfFloat short x, @HalfFloat short y) {
return FP16.max(x, y);
}
/**
* Returns true if the first half-precision float value is less (smaller
* toward negative infinity) than the second half-precision float value.
* If either of the values is NaN, the result is false.
*
* @param x The first half-precision value
* @param y The second half-precision value
*
* @return True if x is less than y, false otherwise
*/
public static boolean less(@HalfFloat short x, @HalfFloat short y) {
return FP16.less(x, y);
}
/**
* Returns true if the first half-precision float value is less (smaller
* toward negative infinity) than or equal to the second half-precision
* float value. If either of the values is NaN, the result is false.
*
* @param x The first half-precision value
* @param y The second half-precision value
*
* @return True if x is less than or equal to y, false otherwise
*/
public static boolean lessEquals(@HalfFloat short x, @HalfFloat short y) {
return FP16.lessEquals(x, y);
}
/**
* Returns true if the first half-precision float value is greater (larger
* toward positive infinity) than the second half-precision float value.
* If either of the values is NaN, the result is false.
*
* @param x The first half-precision value
* @param y The second half-precision value
*
* @return True if x is greater than y, false otherwise
*/
public static boolean greater(@HalfFloat short x, @HalfFloat short y) {
return FP16.greater(x, y);
}
/**
* Returns true if the first half-precision float value is greater (larger
* toward positive infinity) than or equal to the second half-precision float
* value. If either of the values is NaN, the result is false.
*
* @param x The first half-precision value
* @param y The second half-precision value
*
* @return True if x is greater than y, false otherwise
*/
public static boolean greaterEquals(@HalfFloat short x, @HalfFloat short y) {
return FP16.greaterEquals(x, y);
}
/**
* Returns true if the two half-precision float values are equal.
* If either of the values is NaN, the result is false. {@link #POSITIVE_ZERO}
* and {@link #NEGATIVE_ZERO} are considered equal.
*
* @param x The first half-precision value
* @param y The second half-precision value
*
* @return True if x is equal to y, false otherwise
*/
public static boolean equals(@HalfFloat short x, @HalfFloat short y) {
return FP16.equals(x, y);
}
/**
* Returns the sign of the specified half-precision float.
*
* @param h A half-precision float value
* @return 1 if the value is positive, -1 if the value is negative
*/
public static int getSign(@HalfFloat short h) {
return (h & FP16.SIGN_MASK) == 0 ? 1 : -1;
}
/**
* Returns the unbiased exponent used in the representation of
* the specified half-precision float value. if the value is NaN
* or infinite, this* method returns {@link #MAX_EXPONENT} + 1.
* If the argument is 0 or a subnormal representation, this method
* returns {@link #MIN_EXPONENT} - 1.
*
* @param h A half-precision float value
* @return The unbiased exponent of the specified value
*/
public static int getExponent(@HalfFloat short h) {
return ((h >>> FP16.EXPONENT_SHIFT) & FP16.SHIFTED_EXPONENT_MASK) - FP16.EXPONENT_BIAS;
}
/**
* Returns the significand, or mantissa, used in the representation
* of the specified half-precision float value.
*
* @param h A half-precision float value
* @return The significand, or significand, of the specified vlaue
*/
public static int getSignificand(@HalfFloat short h) {
return h & FP16.SIGNIFICAND_MASK;
}
/**
* Returns true if the specified half-precision float value represents
* infinity, false otherwise.
*
* @param h A half-precision float value
* @return True if the value is positive infinity or negative infinity,
* false otherwise
*/
public static boolean isInfinite(@HalfFloat short h) {
return FP16.isInfinite(h);
}
/**
* Returns true if the specified half-precision float value represents
* a Not-a-Number, false otherwise.
*
* @param h A half-precision float value
* @return True if the value is a NaN, false otherwise
*/
public static boolean isNaN(@HalfFloat short h) {
return FP16.isNaN(h);
}
/**
* Returns true if the specified half-precision float value is normalized
* (does not have a subnormal representation). If the specified value is
* {@link #POSITIVE_INFINITY}, {@link #NEGATIVE_INFINITY},
* {@link #POSITIVE_ZERO}, {@link #NEGATIVE_ZERO}, NaN or any subnormal
* number, this method returns false.
*
* @param h A half-precision float value
* @return True if the value is normalized, false otherwise
*/
public static boolean isNormalized(@HalfFloat short h) {
return FP16.isNormalized(h);
}
/**
* Converts the specified half-precision float value into a
* single-precision float value. The following special cases are handled:
*
* - If the input is {@link #NaN}, the returned value is {@link Float#NaN}
* - If the input is {@link #POSITIVE_INFINITY} or
* {@link #NEGATIVE_INFINITY}, the returned value is respectively
* {@link Float#POSITIVE_INFINITY} or {@link Float#NEGATIVE_INFINITY}
* - If the input is 0 (positive or negative), the returned value is +/-0.0f
* - Otherwise, the returned value is a normalized single-precision float value
*
*
* @param h The half-precision float value to convert to single-precision
* @return A normalized single-precision float value
*/
public static float toFloat(@HalfFloat short h) {
return FP16.toFloat(h);
}
/**
* Converts the specified single-precision float value into a
* half-precision float value. The following special cases are handled:
*
* - If the input is NaN (see {@link Float#isNaN(float)}), the returned
* value is {@link #NaN}
* - If the input is {@link Float#POSITIVE_INFINITY} or
* {@link Float#NEGATIVE_INFINITY}, the returned value is respectively
* {@link #POSITIVE_INFINITY} or {@link #NEGATIVE_INFINITY}
* - If the input is 0 (positive or negative), the returned value is
* {@link #POSITIVE_ZERO} or {@link #NEGATIVE_ZERO}
* - If the input is a less than {@link #MIN_VALUE}, the returned value
* is flushed to {@link #POSITIVE_ZERO} or {@link #NEGATIVE_ZERO}
* - If the input is a less than {@link #MIN_NORMAL}, the returned value
* is a denorm half-precision float
* - Otherwise, the returned value is rounded to the nearest
* representable half-precision float value
*
*
* @param f The single-precision float value to convert to half-precision
* @return A half-precision float value
*/
@SuppressWarnings("StatementWithEmptyBody")
public static @HalfFloat short toHalf(float f) {
return FP16.toHalf(f);
}
/**
* Returns a {@code Half} instance representing the specified
* half-precision float value.
*
* @param h A half-precision float value
* @return a {@code Half} instance representing {@code h}
*/
public static @NonNull Half valueOf(@HalfFloat short h) {
return new Half(h);
}
/**
* Returns a {@code Half} instance representing the specified float value.
*
* @param f A float value
* @return a {@code Half} instance representing {@code f}
*/
public static @NonNull Half valueOf(float f) {
return new Half(f);
}
/**
* Returns a {@code Half} instance representing the specified string value.
* Calling this method is equivalent to calling
* toHalf(Float.parseString(h)). See {@link Float#valueOf(String)}
* for more information on the format of the string representation.
*
* @param s The string to be parsed
* @return a {@code Half} instance representing {@code h}
* @throws NumberFormatException if the string does not contain a parsable
* half-precision float value
*/
public static @NonNull Half valueOf(@NonNull String s) {
return new Half(s);
}
/**
* Returns the half-precision float value represented by the specified string.
* Calling this method is equivalent to calling
* toHalf(Float.parseString(h)). See {@link Float#valueOf(String)}
* for more information on the format of the string representation.
*
* @param s The string to be parsed
* @return A half-precision float value represented by the string
* @throws NumberFormatException if the string does not contain a parsable
* half-precision float value
*/
public static @HalfFloat short parseHalf(@NonNull String s) throws NumberFormatException {
return toHalf(Float.parseFloat(s));
}
/**
* Returns a string representation of the specified half-precision
* float value. Calling this method is equivalent to calling
* Float.toString(toFloat(h)). See {@link Float#toString(float)}
* for more information on the format of the string representation.
*
* @param h A half-precision float value
* @return A string representation of the specified value
*/
@NonNull
public static String toString(@HalfFloat short h) {
return Float.toString(toFloat(h));
}
/**
* Returns a hexadecimal string representation of the specified half-precision
* float value. If the value is a NaN, the result is "NaN",
* otherwise the result follows this format:
*
* - If the sign is positive, no sign character appears in the result
* - If the sign is negative, the first character is
'-'
* - If the value is inifinity, the string is
"Infinity"
* - If the value is 0, the string is
"0x0.0p0"
* - If the value has a normalized representation, the exponent and
* significand are represented in the string in two fields. The significand
* starts with
"0x1." followed by its lowercase hexadecimal
* representation. Trailing zeroes are removed unless all digits are 0, then
* a single zero is used. The significand representation is followed by the
* exponent, represented by "p", itself followed by a decimal
* string of the unbiased exponent
* - If the value has a subnormal representation, the significand starts
* with
"0x0." followed by its lowercase hexadecimal
* representation. Trailing zeroes are removed unless all digits are 0, then
* a single zero is used. The significand representation is followed by the
* exponent, represented by "p-14"
*
*
* @param h A half-precision float value
* @return A hexadecimal string representation of the specified value
*/
@NonNull
public static String toHexString(@HalfFloat short h) {
return FP16.toHexString(h);
}
}