src/share/classes/sun/misc/FpUtils.java

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*** 1,7 **** /* ! * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this --- 1,7 ---- /* ! * Copyright (c) 2003, 2011, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this
*** 123,187 **** /** * Don't let anyone instantiate this class. */ private FpUtils() {} - // Constants used in scalb - static double twoToTheDoubleScaleUp = powerOfTwoD(512); - static double twoToTheDoubleScaleDown = powerOfTwoD(-512); - // Helper Methods // The following helper methods are used in the implementation of // the public recommended functions; they generally omit certain // tests for exception cases. /** * Returns unbiased exponent of a {@code double}. */ public static int getExponent(double d){ ! /* ! * Bitwise convert d to long, mask out exponent bits, shift ! * to the right and then subtract out double's bias adjust to ! * get true exponent value. ! */ ! return (int)(((Double.doubleToRawLongBits(d) & DoubleConsts.EXP_BIT_MASK) >> ! (DoubleConsts.SIGNIFICAND_WIDTH - 1)) - DoubleConsts.EXP_BIAS); } /** * Returns unbiased exponent of a {@code float}. */ public static int getExponent(float f){ ! /* ! * Bitwise convert f to integer, mask out exponent bits, shift ! * to the right and then subtract out float's bias adjust to ! * get true exponent value ! */ ! return ((Float.floatToRawIntBits(f) & FloatConsts.EXP_BIT_MASK) >> ! (FloatConsts.SIGNIFICAND_WIDTH - 1)) - FloatConsts.EXP_BIAS; } - /** - * Returns a floating-point power of two in the normal range. - */ - static double powerOfTwoD(int n) { - assert(n >= DoubleConsts.MIN_EXPONENT && n <= DoubleConsts.MAX_EXPONENT); - return Double.longBitsToDouble((((long)n + (long)DoubleConsts.EXP_BIAS) << - (DoubleConsts.SIGNIFICAND_WIDTH-1)) - & DoubleConsts.EXP_BIT_MASK); - } - - /** - * Returns a floating-point power of two in the normal range. - */ - static float powerOfTwoF(int n) { - assert(n >= FloatConsts.MIN_EXPONENT && n <= FloatConsts.MAX_EXPONENT); - return Float.intBitsToFloat(((n + FloatConsts.EXP_BIAS) << - (FloatConsts.SIGNIFICAND_WIDTH-1)) - & FloatConsts.EXP_BIT_MASK); - } /** * Returns the first floating-point argument with the sign of the * second floating-point argument. Note that unlike the {@link * FpUtils#copySign(double, double) copySign} method, this method --- 123,156 ---- /** * Don't let anyone instantiate this class. */ private FpUtils() {} // Helper Methods // The following helper methods are used in the implementation of // the public recommended functions; they generally omit certain // tests for exception cases. /** * Returns unbiased exponent of a {@code double}. + * @deprecated Use Math.getExponent. */ + @Deprecated public static int getExponent(double d){ ! return Math.getExponent(d); } /** * Returns unbiased exponent of a {@code float}. + * @deprecated Use Math.getExponent. */ + @Deprecated public static int getExponent(float f){ ! return Math.getExponent(f); } /** * Returns the first floating-point argument with the sign of the * second floating-point argument. Note that unlike the {@link * FpUtils#copySign(double, double) copySign} method, this method
*** 193,209 **** * @param magnitude the parameter providing the magnitude of the result * @param sign the parameter providing the sign of the result * @return a value with the magnitude of {@code magnitude} * and the sign of {@code sign}. * @author Joseph D. Darcy */ public static double rawCopySign(double magnitude, double sign) { ! return Double.longBitsToDouble((Double.doubleToRawLongBits(sign) & ! (DoubleConsts.SIGN_BIT_MASK)) | ! (Double.doubleToRawLongBits(magnitude) & ! (DoubleConsts.EXP_BIT_MASK | ! DoubleConsts.SIGNIF_BIT_MASK))); } /** * Returns the first floating-point argument with the sign of the * second floating-point argument. Note that unlike the {@link --- 162,176 ---- * @param magnitude the parameter providing the magnitude of the result * @param sign the parameter providing the sign of the result * @return a value with the magnitude of {@code magnitude} * and the sign of {@code sign}. * @author Joseph D. Darcy + * @deprecated Use Math.copySign. */ + @Deprecated public static double rawCopySign(double magnitude, double sign) { ! return Math.copySign(magnitude, sign); } /** * Returns the first floating-point argument with the sign of the * second floating-point argument. Note that unlike the {@link
*** 216,232 **** * @param magnitude the parameter providing the magnitude of the result * @param sign the parameter providing the sign of the result * @return a value with the magnitude of {@code magnitude} * and the sign of {@code sign}. * @author Joseph D. Darcy */ public static float rawCopySign(float magnitude, float sign) { ! return Float.intBitsToFloat((Float.floatToRawIntBits(sign) & ! (FloatConsts.SIGN_BIT_MASK)) | ! (Float.floatToRawIntBits(magnitude) & ! (FloatConsts.EXP_BIT_MASK | ! FloatConsts.SIGNIF_BIT_MASK))); } /* ***************************************************************** */ /** --- 183,197 ---- * @param magnitude the parameter providing the magnitude of the result * @param sign the parameter providing the sign of the result * @return a value with the magnitude of {@code magnitude} * and the sign of {@code sign}. * @author Joseph D. Darcy + * @deprecated Use Math.copySign. */ + @Deprecated public static float rawCopySign(float magnitude, float sign) { ! return Math.copySign(magnitude, sign); } /* ***************************************************************** */ /**
*** 556,641 **** * * @param d number to be scaled by a power of two. * @param scale_factor power of 2 used to scale {@code d} * @return {@code d * }2<sup>{@code scale_factor}</sup> * @author Joseph D. Darcy */ public static double scalb(double d, int scale_factor) { ! /* ! * This method does not need to be declared strictfp to ! * compute the same correct result on all platforms. When ! * scaling up, it does not matter what order the ! * multiply-store operations are done; the result will be ! * finite or overflow regardless of the operation ordering. ! * However, to get the correct result when scaling down, a ! * particular ordering must be used. ! * ! * When scaling down, the multiply-store operations are ! * sequenced so that it is not possible for two consecutive ! * multiply-stores to return subnormal results. If one ! * multiply-store result is subnormal, the next multiply will ! * round it away to zero. This is done by first multiplying ! * by 2 ^ (scale_factor % n) and then multiplying several ! * times by by 2^n as needed where n is the exponent of number ! * that is a covenient power of two. In this way, at most one ! * real rounding error occurs. If the double value set is ! * being used exclusively, the rounding will occur on a ! * multiply. If the double-extended-exponent value set is ! * being used, the products will (perhaps) be exact but the ! * stores to d are guaranteed to round to the double value ! * set. ! * ! * It is _not_ a valid implementation to first multiply d by ! * 2^MIN_EXPONENT and then by 2 ^ (scale_factor % ! * MIN_EXPONENT) since even in a strictfp program double ! * rounding on underflow could occur; e.g. if the scale_factor ! * argument was (MIN_EXPONENT - n) and the exponent of d was a ! * little less than -(MIN_EXPONENT - n), meaning the final ! * result would be subnormal. ! * ! * Since exact reproducibility of this method can be achieved ! * without any undue performance burden, there is no ! * compelling reason to allow double rounding on underflow in ! * scalb. ! */ ! ! // magnitude of a power of two so large that scaling a finite ! // nonzero value by it would be guaranteed to over or ! // underflow; due to rounding, scaling down takes takes an ! // additional power of two which is reflected here ! final int MAX_SCALE = DoubleConsts.MAX_EXPONENT + -DoubleConsts.MIN_EXPONENT + ! DoubleConsts.SIGNIFICAND_WIDTH + 1; ! int exp_adjust = 0; ! int scale_increment = 0; ! double exp_delta = Double.NaN; ! ! // Make sure scaling factor is in a reasonable range ! ! if(scale_factor < 0) { ! scale_factor = Math.max(scale_factor, -MAX_SCALE); ! scale_increment = -512; ! exp_delta = twoToTheDoubleScaleDown; ! } ! else { ! scale_factor = Math.min(scale_factor, MAX_SCALE); ! scale_increment = 512; ! exp_delta = twoToTheDoubleScaleUp; ! } ! ! // Calculate (scale_factor % +/-512), 512 = 2^9, using ! // technique from "Hacker's Delight" section 10-2. ! int t = (scale_factor >> 9-1) >>> 32 - 9; ! exp_adjust = ((scale_factor + t) & (512 -1)) - t; ! ! d *= powerOfTwoD(exp_adjust); ! scale_factor -= exp_adjust; ! ! while(scale_factor != 0) { ! d *= exp_delta; ! scale_factor -= scale_increment; ! } ! return d; } /** * Return {@code f} &times; * 2<sup>{@code scale_factor}</sup> rounded as if performed --- 521,535 ---- * * @param d number to be scaled by a power of two. * @param scale_factor power of 2 used to scale {@code d} * @return {@code d * }2<sup>{@code scale_factor}</sup> * @author Joseph D. Darcy + * @deprecated Use Math.scalb. */ + @Deprecated public static double scalb(double d, int scale_factor) { ! return Math.scalb(d, scale_factor); } /** * Return {@code f} &times; * 2<sup>{@code scale_factor}</sup> rounded as if performed
*** 665,696 **** * * @param f number to be scaled by a power of two. * @param scale_factor power of 2 used to scale {@code f} * @return {@code f * }2<sup>{@code scale_factor}</sup> * @author Joseph D. Darcy */ public static float scalb(float f, int scale_factor) { ! // magnitude of a power of two so large that scaling a finite ! // nonzero value by it would be guaranteed to over or ! // underflow; due to rounding, scaling down takes takes an ! // additional power of two which is reflected here ! final int MAX_SCALE = FloatConsts.MAX_EXPONENT + -FloatConsts.MIN_EXPONENT + ! FloatConsts.SIGNIFICAND_WIDTH + 1; ! ! // Make sure scaling factor is in a reasonable range ! scale_factor = Math.max(Math.min(scale_factor, MAX_SCALE), -MAX_SCALE); ! ! /* ! * Since + MAX_SCALE for float fits well within the double ! * exponent range and + float -> double conversion is exact ! * the multiplication below will be exact. Therefore, the ! * rounding that occurs when the double product is cast to ! * float will be the correctly rounded float result. Since ! * all operations other than the final multiply will be exact, ! * it is not necessary to declare this method strictfp. ! */ ! return (float)((double)f*powerOfTwoD(scale_factor)); } /** * Returns the floating-point number adjacent to the first * argument in the direction of the second argument. If both --- 559,573 ---- * * @param f number to be scaled by a power of two. * @param scale_factor power of 2 used to scale {@code f} * @return {@code f * }2<sup>{@code scale_factor}</sup> * @author Joseph D. Darcy + * @deprecated Use Math.scalb. */ + @Deprecated public static float scalb(float f, int scale_factor) { ! return Math.scalb(f, scale_factor); } /** * Returns the floating-point number adjacent to the first * argument in the direction of the second argument. If both
*** 728,796 **** * {@code start}'s neighbors or {@code start} should * be returned * @return The floating-point number adjacent to {@code start} in the * direction of {@code direction}. * @author Joseph D. Darcy */ public static double nextAfter(double start, double direction) { ! /* ! * The cases: ! * ! * nextAfter(+infinity, 0) == MAX_VALUE ! * nextAfter(+infinity, +infinity) == +infinity ! * nextAfter(-infinity, 0) == -MAX_VALUE ! * nextAfter(-infinity, -infinity) == -infinity ! * ! * are naturally handled without any additional testing ! */ ! ! // First check for NaN values ! if (isNaN(start) || isNaN(direction)) { ! // return a NaN derived from the input NaN(s) ! return start + direction; ! } else if (start == direction) { ! return direction; ! } else { // start > direction or start < direction ! // Add +0.0 to get rid of a -0.0 (+0.0 + -0.0 => +0.0) ! // then bitwise convert start to integer. ! long transducer = Double.doubleToRawLongBits(start + 0.0d); ! ! /* ! * IEEE 754 floating-point numbers are lexicographically ! * ordered if treated as signed- magnitude integers . ! * Since Java's integers are two's complement, ! * incrementing" the two's complement representation of a ! * logically negative floating-point value *decrements* ! * the signed-magnitude representation. Therefore, when ! * the integer representation of a floating-point values ! * is less than zero, the adjustment to the representation ! * is in the opposite direction than would be expected at ! * first . ! */ ! if (direction > start) { // Calculate next greater value ! transducer = transducer + (transducer >= 0L ? 1L:-1L); ! } else { // Calculate next lesser value ! assert direction < start; ! if (transducer > 0L) ! --transducer; ! else ! if (transducer < 0L ) ! ++transducer; ! /* ! * transducer==0, the result is -MIN_VALUE ! * ! * The transition from zero (implicitly ! * positive) to the smallest negative ! * signed magnitude value must be done ! * explicitly. ! */ ! else ! transducer = DoubleConsts.SIGN_BIT_MASK | 1L; ! } ! ! return Double.longBitsToDouble(transducer); ! } } /** * Returns the floating-point number adjacent to the first * argument in the direction of the second argument. If both --- 605,619 ---- * {@code start}'s neighbors or {@code start} should * be returned * @return The floating-point number adjacent to {@code start} in the * direction of {@code direction}. * @author Joseph D. Darcy + * @deprecated Use Math.nextAfter */ + @Deprecated public static double nextAfter(double start, double direction) { ! return Math.nextAfter(start, direction); } /** * Returns the floating-point number adjacent to the first * argument in the direction of the second argument. If both
*** 828,896 **** * {@code start}'s neighbors or {@code start} should * be returned * @return The floating-point number adjacent to {@code start} in the * direction of {@code direction}. * @author Joseph D. Darcy */ public static float nextAfter(float start, double direction) { ! /* ! * The cases: ! * ! * nextAfter(+infinity, 0) == MAX_VALUE ! * nextAfter(+infinity, +infinity) == +infinity ! * nextAfter(-infinity, 0) == -MAX_VALUE ! * nextAfter(-infinity, -infinity) == -infinity ! * ! * are naturally handled without any additional testing ! */ ! ! // First check for NaN values ! if (isNaN(start) || isNaN(direction)) { ! // return a NaN derived from the input NaN(s) ! return start + (float)direction; ! } else if (start == direction) { ! return (float)direction; ! } else { // start > direction or start < direction ! // Add +0.0 to get rid of a -0.0 (+0.0 + -0.0 => +0.0) ! // then bitwise convert start to integer. ! int transducer = Float.floatToRawIntBits(start + 0.0f); ! ! /* ! * IEEE 754 floating-point numbers are lexicographically ! * ordered if treated as signed- magnitude integers . ! * Since Java's integers are two's complement, ! * incrementing" the two's complement representation of a ! * logically negative floating-point value *decrements* ! * the signed-magnitude representation. Therefore, when ! * the integer representation of a floating-point values ! * is less than zero, the adjustment to the representation ! * is in the opposite direction than would be expected at ! * first. ! */ ! if (direction > start) {// Calculate next greater value ! transducer = transducer + (transducer >= 0 ? 1:-1); ! } else { // Calculate next lesser value ! assert direction < start; ! if (transducer > 0) ! --transducer; ! else ! if (transducer < 0 ) ! ++transducer; ! /* ! * transducer==0, the result is -MIN_VALUE ! * ! * The transition from zero (implicitly ! * positive) to the smallest negative ! * signed magnitude value must be done ! * explicitly. ! */ ! else ! transducer = FloatConsts.SIGN_BIT_MASK | 1; ! } ! ! return Float.intBitsToFloat(transducer); ! } } /** * Returns the floating-point value adjacent to {@code d} in * the direction of positive infinity. This method is --- 651,665 ---- * {@code start}'s neighbors or {@code start} should * be returned * @return The floating-point number adjacent to {@code start} in the * direction of {@code direction}. * @author Joseph D. Darcy + * @deprecated Use Math.nextAfter. */ + @Deprecated public static float nextAfter(float start, double direction) { ! return Math.nextAfter(start, direction); } /** * Returns the floating-point value adjacent to {@code d} in * the direction of positive infinity. This method is
*** 913,931 **** * * @param d starting floating-point value * @return The adjacent floating-point value closer to positive * infinity. * @author Joseph D. Darcy */ public static double nextUp(double d) { ! if( isNaN(d) || d == Double.POSITIVE_INFINITY) ! return d; ! else { ! d += 0.0d; ! return Double.longBitsToDouble(Double.doubleToRawLongBits(d) + ! ((d >= 0.0d)?+1L:-1L)); ! } } /** * Returns the floating-point value adjacent to {@code f} in * the direction of positive infinity. This method is --- 682,696 ---- * * @param d starting floating-point value * @return The adjacent floating-point value closer to positive * infinity. * @author Joseph D. Darcy + * @deprecated use Math.nextUp. */ + @Deprecated public static double nextUp(double d) { ! return Math.nextUp(d); } /** * Returns the floating-point value adjacent to {@code f} in * the direction of positive infinity. This method is
*** 948,966 **** * * @param f starting floating-point value * @return The adjacent floating-point value closer to positive * infinity. * @author Joseph D. Darcy */ public static float nextUp(float f) { ! if( isNaN(f) || f == FloatConsts.POSITIVE_INFINITY) ! return f; ! else { ! f += 0.0f; ! return Float.intBitsToFloat(Float.floatToRawIntBits(f) + ! ((f >= 0.0f)?+1:-1)); ! } } /** * Returns the floating-point value adjacent to {@code d} in * the direction of negative infinity. This method is --- 713,727 ---- * * @param f starting floating-point value * @return The adjacent floating-point value closer to positive * infinity. * @author Joseph D. Darcy + * @deprecated Use Math.nextUp. */ + @Deprecated public static float nextUp(float f) { ! return Math.nextUp(f); } /** * Returns the floating-point value adjacent to {@code d} in * the direction of negative infinity. This method is
*** 1045,1057 **** * @param sign the parameter providing the sign of the result * @return a value with the magnitude of {@code magnitude} * and the sign of {@code sign}. * @author Joseph D. Darcy * @since 1.5 */ public static double copySign(double magnitude, double sign) { ! return rawCopySign(magnitude, (isNaN(sign)?1.0d:sign)); } /** * Returns the first floating-point argument with the sign of the * second floating-point argument. For this method, a NaN --- 806,820 ---- * @param sign the parameter providing the sign of the result * @return a value with the magnitude of {@code magnitude} * and the sign of {@code sign}. * @author Joseph D. Darcy * @since 1.5 + * @deprecated Use StrictMath.copySign. */ + @Deprecated public static double copySign(double magnitude, double sign) { ! return StrictMath.copySign(magnitude, sign); } /** * Returns the first floating-point argument with the sign of the * second floating-point argument. For this method, a NaN
*** 1061,1073 **** * @param magnitude the parameter providing the magnitude of the result * @param sign the parameter providing the sign of the result * @return a value with the magnitude of {@code magnitude} * and the sign of {@code sign}. * @author Joseph D. Darcy */ public static float copySign(float magnitude, float sign) { ! return rawCopySign(magnitude, (isNaN(sign)?1.0f:sign)); } /** * Returns the size of an ulp of the argument. An ulp of a * {@code double} value is the positive distance between this --- 824,838 ---- * @param magnitude the parameter providing the magnitude of the result * @param sign the parameter providing the sign of the result * @return a value with the magnitude of {@code magnitude} * and the sign of {@code sign}. * @author Joseph D. Darcy + * @deprecated Use StrictMath.copySign. */ + @Deprecated public static float copySign(float magnitude, float sign) { ! return StrictMath.copySign(magnitude, sign); } /** * Returns the size of an ulp of the argument. An ulp of a * {@code double} value is the positive distance between this
*** 1088,1124 **** * * @param d the floating-point value whose ulp is to be returned * @return the size of an ulp of the argument * @author Joseph D. Darcy * @since 1.5 */ public static double ulp(double d) { ! int exp = getExponent(d); ! ! switch(exp) { ! case DoubleConsts.MAX_EXPONENT+1: // NaN or infinity ! return Math.abs(d); ! ! case DoubleConsts.MIN_EXPONENT-1: // zero or subnormal ! return Double.MIN_VALUE; ! ! default: ! assert exp <= DoubleConsts.MAX_EXPONENT && exp >= DoubleConsts.MIN_EXPONENT; ! ! // ulp(x) is usually 2^(SIGNIFICAND_WIDTH-1)*(2^ilogb(x)) ! exp = exp - (DoubleConsts.SIGNIFICAND_WIDTH-1); ! if (exp >= DoubleConsts.MIN_EXPONENT) { ! return powerOfTwoD(exp); ! } ! else { ! // return a subnormal result; left shift integer ! // representation of Double.MIN_VALUE appropriate ! // number of positions ! return Double.longBitsToDouble(1L << ! (exp - (DoubleConsts.MIN_EXPONENT - (DoubleConsts.SIGNIFICAND_WIDTH-1)) )); ! } ! } } /** * Returns the size of an ulp of the argument. An ulp of a * {@code float} value is the positive distance between this --- 853,867 ---- * * @param d the floating-point value whose ulp is to be returned * @return the size of an ulp of the argument * @author Joseph D. Darcy * @since 1.5 + * @deprecated Use Math.ulp. */ + @Deprecated public static double ulp(double d) { ! return Math.ulp(d); } /** * Returns the size of an ulp of the argument. An ulp of a * {@code float} value is the positive distance between this
*** 1139,1175 **** * * @param f the floating-point value whose ulp is to be returned * @return the size of an ulp of the argument * @author Joseph D. Darcy * @since 1.5 */ public static float ulp(float f) { ! int exp = getExponent(f); ! ! switch(exp) { ! case FloatConsts.MAX_EXPONENT+1: // NaN or infinity ! return Math.abs(f); ! ! case FloatConsts.MIN_EXPONENT-1: // zero or subnormal ! return FloatConsts.MIN_VALUE; ! ! default: ! assert exp <= FloatConsts.MAX_EXPONENT && exp >= FloatConsts.MIN_EXPONENT; ! ! // ulp(x) is usually 2^(SIGNIFICAND_WIDTH-1)*(2^ilogb(x)) ! exp = exp - (FloatConsts.SIGNIFICAND_WIDTH-1); ! if (exp >= FloatConsts.MIN_EXPONENT) { ! return powerOfTwoF(exp); ! } ! else { ! // return a subnormal result; left shift integer ! // representation of FloatConsts.MIN_VALUE appropriate ! // number of positions ! return Float.intBitsToFloat(1 << ! (exp - (FloatConsts.MIN_EXPONENT - (FloatConsts.SIGNIFICAND_WIDTH-1)) )); ! } ! } } /** * Returns the signum function of the argument; zero if the argument * is zero, 1.0 if the argument is greater than zero, -1.0 if the --- 882,896 ---- * * @param f the floating-point value whose ulp is to be returned * @return the size of an ulp of the argument * @author Joseph D. Darcy * @since 1.5 + * @deprecated Use Math.ulp. */ + @Deprecated public static float ulp(float f) { ! return Math.ulp(f); } /** * Returns the signum function of the argument; zero if the argument * is zero, 1.0 if the argument is greater than zero, -1.0 if the
*** 1184,1196 **** * * @param d the floating-point value whose signum is to be returned * @return the signum function of the argument * @author Joseph D. Darcy * @since 1.5 */ public static double signum(double d) { ! return (d == 0.0 || isNaN(d))?d:copySign(1.0, d); } /** * Returns the signum function of the argument; zero if the argument * is zero, 1.0f if the argument is greater than zero, -1.0f if the --- 905,919 ---- * * @param d the floating-point value whose signum is to be returned * @return the signum function of the argument * @author Joseph D. Darcy * @since 1.5 + * @deprecated Use Math.signum. */ + @Deprecated public static double signum(double d) { ! return Math.signum(d); } /** * Returns the signum function of the argument; zero if the argument * is zero, 1.0f if the argument is greater than zero, -1.0f if the
*** 1205,1215 **** * * @param f the floating-point value whose signum is to be returned * @return the signum function of the argument * @author Joseph D. Darcy * @since 1.5 */ public static float signum(float f) { ! return (f == 0.0f || isNaN(f))?f:copySign(1.0f, f); } - } --- 928,939 ---- * * @param f the floating-point value whose signum is to be returned * @return the signum function of the argument * @author Joseph D. Darcy * @since 1.5 + * @deprecated Use Math.signum. */ + @Deprecated public static float signum(float f) { ! return Math.signum(f); } }