Example usage for java.lang Math nextAfter

List of usage examples for java.lang Math nextAfter

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Introduction

In this page you can find the example usage for java.lang Math nextAfter.

Prototype

public static float nextAfter(float start, double direction)

Source Link

Document

Returns the floating-point number adjacent to the first argument in the direction of the second argument.

Usage

From source file:FloastPointDemo.java

public static void main(String[] args) {
    // Returns the lesser adjacent of a double
    double lesserAdjacent = Math.nextAfter(123.0, 120.0);
    System.out.println("Math.nextAfter (123.0, 120.0) = " + lesserAdjacent);
}

From source file:Main.java

public static void main(String[] args) {
    double x = 123456.7;
    double y = -123.45;

    // print the next number for x towards y
    System.out.println("Math.nextAfter(" + x + "," + y + ")=" + Math.nextAfter(x, y));

    // print the next number for y towards x
    System.out.println("Math.nextAfter(" + y + "," + x + ")=" + Math.nextAfter(y, x));

}

From source file:Main.java

public static void main(String[] args) {

    float x = 12345.123f;
    double y = 123.12345;

    // print the next number for x towards y
    System.out.println("Math.nextAfter(" + x + "," + y + ")=" + Math.nextAfter(x, y));

}

From source file:org.asoem.greyfish.core.space.WalledPointSpace.java

/**
 * Checks if the line {@code xo, yo, xd, yd} crosses an edge of the {@code tile} or any adjacent tile in the
 * direction of movement which has a wall present. If such a crossing is found, than the point closest to this
 * crossing is returned, {@code null}, otherwise.
 *
 * @param tile the tile to check for a collision
 * @param xo   Movement line x origin/*from   ww  w  .  j av a  2  s . c  o m*/
 * @param yo   Movement line y origin
 * @param xd   Movement line x destination
 * @param yd   Movement line x destination
 * @return the location on the line closest to the point of a collision with a wall or {@code null} if none could be
 * found
 */
@Nullable
private Point2D collision(final WalledTile tile, final double xo, final double yo, final double xd,
        final double yd) {
    assert tile != null;

    if (tile.covers(xd, yd)) {
        return null;
    }

    TileDirection follow1 = null;
    TileDirection follow2 = null;

    if (yd < yo) { // north
        final ImmutablePoint2D intersection = intersection(tile.getX(), tile.getY(),
                Math.nextAfter(tile.getX() + 1.0, -Double.MIN_VALUE), tile.getY(), xo, yo, xd, yd);

        if (intersection != null) {
            if (tile.hasWall(TileDirection.NORTH)) {
                return intersection;
            } else {
                follow1 = TileDirection.NORTH;
            }
        }
    }

    if (xd > xo) { // east
        final ImmutablePoint2D intersection = intersection(Math.nextAfter(tile.getX() + 1.0, -Double.MIN_VALUE),
                tile.getY(), Math.nextAfter(tile.getX() + 1.0, -Double.MIN_VALUE),
                Math.nextAfter(tile.getY() + 1.0, -Double.MIN_VALUE), xo, yo, xd, yd);

        if (intersection != null) {
            if (tile.hasWall(TileDirection.EAST)) {
                return intersection;
            } else {
                if (follow1 == null) {
                    follow1 = TileDirection.EAST;
                } else {
                    follow2 = TileDirection.EAST;
                }
            }
        }
    }

    if (yd > yo) { // south
        final ImmutablePoint2D intersection = intersection(tile.getX(),
                Math.nextAfter(tile.getY() + 1.0, -Double.MIN_VALUE),
                Math.nextAfter(tile.getX() + 1.0, -Double.MIN_VALUE),
                Math.nextAfter(tile.getY() + 1.0, -Double.MIN_VALUE), xo, yo, xd, yd);

        if (intersection != null) {
            if (tile.hasWall(TileDirection.SOUTH)) {
                return intersection;
            } else {
                if (follow1 == null) {
                    follow1 = TileDirection.SOUTH;
                } else {
                    follow2 = TileDirection.SOUTH;
                }
            }
        }
    }

    if (xd < xo) { // west
        final ImmutablePoint2D intersection = intersection(tile.getX(),
                Math.nextAfter(tile.getY() + 1.0, -Double.MIN_VALUE), tile.getX(), tile.getY(), xo, yo, xd, yd);

        if (intersection != null) {
            if (tile.hasWall(TileDirection.WEST)) {
                return intersection;
            } else {
                if (follow1 == null) {
                    follow1 = TileDirection.WEST;
                } else {
                    follow2 = TileDirection.WEST;
                }
            }
        }
    }

    if (follow1 != null && hasAdjacentTile(tile, follow1)) {
        final Point2D collision = collision(getAdjacentTile(tile, follow1), xo, yo, xd, yd);
        if (collision != null) {
            return collision;
        } else if (follow2 != null && hasAdjacentTile(tile, follow2)) {
            final Point2D collision1 = collision(getAdjacentTile(tile, follow2), xo, yo, xd, yd);
            if (collision1 != null) {
                return collision1;
            }
        }
    }

    return null;
}

From source file:org.streaminer.stream.histogram.spdt.Histogram.java

/**
 * Returns a <code>SumResult</code> object which contains the
 * density estimate at the point <code>p</code> along
 * with the density for the targets./*  w  w w . j a  va2  s.  c  om*/
 *
 * @param p the density estimate point
 */
public SumResult<T> extendedDensity(double p) {
    T emptyTarget = (T) _bins.first().getTarget().init();
    double countDensity;
    T targetDensity;

    Bin<T> exact = _bins.get(p);
    if (p < _minimum || p > _maximum) {
        countDensity = 0;
        targetDensity = (T) emptyTarget.clone();
    } else if (p == _minimum && p == _maximum) {
        countDensity = Double.POSITIVE_INFINITY;
        targetDensity = emptyTarget;
    } else if (exact != null) {
        double higher = Math.nextAfter(p, Double.POSITIVE_INFINITY);
        double lower = Math.nextAfter(p, Double.NEGATIVE_INFINITY);

        SumResult<T> lowerResult = extendedDensity(lower);
        SumResult<T> higherResult = extendedDensity(higher);
        countDensity = (lowerResult.getCount() + higherResult.getCount()) / 2;
        targetDensity = (T) lowerResult.getTargetSum().clone().sum(higherResult.getTargetSum()).mult(0.5);
    } else {
        Bin<T> lowerBin = _bins.lower(p);
        if (lowerBin == null) {
            lowerBin = new Bin(_minimum, 0, emptyTarget.clone());
        }

        Bin<T> higherBin = _bins.higher(p);
        if (higherBin == null) {
            higherBin = new Bin(_maximum, 0, emptyTarget.clone());
        }

        double bDiff = p - lowerBin.getMean();
        double pDiff = higherBin.getMean() - lowerBin.getMean();
        double bpRatio = bDiff / pDiff;

        NumericTarget countTarget = (NumericTarget) computeDensity(bpRatio, lowerBin.getMean(),
                higherBin.getMean(), new NumericTarget(lowerBin.getCount()),
                new NumericTarget(higherBin.getCount()));
        countDensity = countTarget.getSum();

        targetDensity = (T) computeDensity(bpRatio, lowerBin.getMean(), higherBin.getMean(),
                lowerBin.getTarget(), higherBin.getTarget());
    }

    return new SumResult<T>(countDensity, targetDensity);
}

From source file:com.bigml.histogram.Histogram.java

/**
 * Returns a <code>SumResult</code> object which contains the
 * density estimate at the point <code>p</code> along
 * with the density for the targets.//from  w  w w .j  av a 2  s .c o  m
 *
 * @param p the density estimate point
 */
@SuppressWarnings("unchecked")
public SumResult<T> extendedDensity(double p) {
    T emptyTarget = (T) _bins.first().getTarget().init();
    double countDensity;
    T targetDensity;

    Bin<T> exact = _bins.get(p);
    if (p < _minimum || p > _maximum) {
        countDensity = 0;
        targetDensity = (T) emptyTarget.clone();
    } else if (p == _minimum && p == _maximum) {
        countDensity = Double.POSITIVE_INFINITY;
        targetDensity = emptyTarget;
    } else if (exact != null) {
        double higher = Math.nextAfter(p, Double.POSITIVE_INFINITY);
        double lower = Math.nextAfter(p, Double.NEGATIVE_INFINITY);

        SumResult<T> lowerResult = extendedDensity(lower);
        SumResult<T> higherResult = extendedDensity(higher);
        countDensity = (lowerResult.getCount() + higherResult.getCount()) / 2;
        targetDensity = (T) lowerResult.getTargetSum().clone().sum(higherResult.getTargetSum()).mult(0.5);
    } else {
        Bin<T> lowerBin = _bins.lower(p);
        if (lowerBin == null) {
            lowerBin = new Bin<T>(_minimum, 0, (T) emptyTarget.clone());
        }

        Bin<T> higherBin = _bins.higher(p);
        if (higherBin == null) {
            higherBin = new Bin<T>(_maximum, 0, (T) emptyTarget.clone());
        }

        double bDiff = p - lowerBin.getMean();
        double pDiff = higherBin.getMean() - lowerBin.getMean();
        double bpRatio = bDiff / pDiff;

        NumericTarget countTarget = (NumericTarget) computeDensity(bpRatio, lowerBin.getMean(),
                higherBin.getMean(), new NumericTarget(lowerBin.getCount()),
                new NumericTarget(higherBin.getCount()));
        countDensity = countTarget.getSum();

        targetDensity = (T) computeDensity(bpRatio, lowerBin.getMean(), higherBin.getMean(),
                lowerBin.getTarget(), higherBin.getTarget());
    }

    return new SumResult<T>(countDensity, targetDensity);
}

From source file:org.opendatakit.services.database.utilities.ODKDatabaseImplUtils.java

public boolean identicalValue(String localValue, String serverValue, ElementDataType dt) {

    if (localValue == null && serverValue == null) {
        return true;
    } else if (localValue == null || serverValue == null) {
        return false;
    } else if (localValue.equals(serverValue)) {
        return true;
    }//from  w  w w .j  a v  a  2 s .  c  o m

    // NOT textually identical.
    //
    // Everything must be textually identical except possibly number fields
    // which may have rounding due to different database implementations,
    // data representations, and marshaling libraries.
    //
    if (dt == ElementDataType.number) {
        // !!Important!! Double.valueOf(str) handles NaN and +/-Infinity
        Double localNumber = Double.valueOf(localValue);
        Double serverNumber = Double.valueOf(serverValue);

        if (localNumber.equals(serverNumber)) {
            // simple case -- trailing zeros or string representation mix-up
            //
            return true;
        } else if (localNumber.isInfinite() && serverNumber.isInfinite()) {
            // if they are both plus or both minus infinity, we have a match
            if (Math.signum(localNumber) == Math.signum(serverNumber)) {
                return true;
            } else {
                return false;
            }
        } else if (localNumber.isNaN() || localNumber.isInfinite() || serverNumber.isNaN()
                || serverNumber.isInfinite()) {
            // one or the other is special1
            return false;
        } else {
            double localDbl = localNumber;
            double serverDbl = serverNumber;
            if (localDbl == serverDbl) {
                return true;
            }
            // OK. We have two values like 9.80 and 9.8
            // consider them equal if they are adjacent to each other.
            double localNear = localDbl;
            int idist = 0;
            int idistMax = 128;
            for (idist = 0; idist < idistMax; ++idist) {
                localNear = Math.nextAfter(localNear, serverDbl);
                if (localNear == serverDbl) {
                    break;
                }
            }
            if (idist < idistMax) {
                return true;
            }
            return false;
        }
    } else {
        // textual identity is required!
        return false;
    }
}