isNaN(float)

isNaN(float)

Declaration:
public static boolean isNaN(float v)
Description:
Returns true if the specified number is the special Not-a-Number (NaN) value.
Parameters:
v - the value to be tested.
Returns: true if the argument is NaN; false otherwise.
isInfinite(float)
Declaration:
public static boolean isInfinite(float v)
Description:
Returns true if the specified number is infinitely large in magnitude.
Parameters:
v - the value to be tested.
Returns: true if the argument is positive infinity or negative infinity; false otherwise.
isNaN()
Declaration:
public boolean isNaN()
Description:
Returns true if this Float value is Not-a-Number (NaN).
Returns: true if the value represented by this object is NaN; false otherwise.
isInfinite()
Declaration:
public boolean isInfinite()
Description:
Returns true if this Float value is infinitely large in magnitude.
Returns: true if the value represented by this object is positive infinity or negative infinity; false
otherwise.


toString()

toString()
Declaration:
public java.lang.String toString()
Description:
Returns a String representation of this Float object. The primitive float value represented by this object is
converted to a String exactly as if by the method toString of one argument.
Overrides: toString in class Object
Returns: a String representation of this object.
See Also: toString(float)
byteValue()
Declaration:
public byte byteValue()
Description:
Returns the value of this Float as a byte (by casting to a byte).
Since: JDK1.1
shortValue()
Declaration:
public short shortValue()
Description:
Returns the value of this Float as a short (by casting to a short).
Since: JDK1.1
intValue()
Declaration:
public int intValue()
Description:
Returns the integer value of this Float (by casting to an int).
Returns: the float value represented by this object converted to type int and the result of the
conversion is returned.
longValue()
Declaration:
public long longValue()
Description:
Returns the long value of this Float (by casting to a long).
Returns: the float value represented by this object is converted to type long and the result of the
conversion is returned.
floatValue()
Declaration:
public float floatValue()

Description:
Returns the float value of this Float object.
Returns: the float value represented by this object.
doubleValue()
Declaration:
public double doubleValue()
Description:
Returns the double value of this Float object.
Returns: the float value represented by this object is converted to type double and the result of the
conversion is returned.
hashCode()
Declaration:
public int hashCode()
Description:
Returns a hashcode for this Float object. The result is the integer bit representation, exactly as produced
by the method floatToIntBits(float), of the primitive float value represented by this Float
object.
Overrides: hashCode in class Object
Returns: a hash code value for this object.
equals(Object)
Declaration:
public boolean equals(java.lang.Object obj)
Description:
Compares this object against some other object. The result is true if and only if the argument is not null
and is a Float object that represents a float that has the identical bit pattern to the bit pattern of the
float represented by this object. For this purpose, two float values are considered to be the same if and
only if the method floatToIntBits(float) returns the same int value when applied to each.
Note that in most cases, for two instances of class Float, f1 and f2, the value of f1.equals(f2) is
true if and only if
f1.floatValue() == f2.floatValue()
also has the value true. However, there are two exceptions:
• If f1 and f2 both represent Float.NaN, then the equals method returns true, even though
Float.NaN==Float.NaN has the value false.
• If f1 represents +0.0f while f2 represents -0.0f, or vice versa, the equal test has the value
false, even though 0.0f==-0.0f has the value true.
This definition allows hashtables to operate properly.
Overrides: equals in class Object
Parameters:
obj - the object to be compared

floatToIntBits(float)

Returns: true if the objects are the same; false otherwise.
See Also: floatToIntBits(float)
floatToIntBits(float)
Declaration:
public static int floatToIntBits(float value)
Description:
Returns the bit representation of a single-float value. The result is a representation of the floating-point
argument according to the IEEE 754 floating-point “single precision” bit layout.
• Bit 31 (the bit that is selected by the mask 0x80000000) represents the sign of the floating-point
number.
• Bits 30-23 (the bits that are selected by the mask 0x7f800000) represent the exponent.
• Bits 22-0 (the bits that are selected by the mask 0x007fffff) represent the significand (sometimes
called the mantissa) of the floating-point number.
• If the argument is positive infinity, the result is 0x7f800000.
• If the argument is negative infinity, the result is 0xff800000.
• If the argument is NaN, the result is 0x7fc00000.
In all cases, the result is an integer that, when given to the intBitsToFloat(int) method, will
produce a floating-point value equal to the argument to floatToIntBits.
Parameters:
value - a floating-point number.
Returns: the bits that represent the floating-point number.
intBitsToFloat(int)
Declaration:
public static float intBitsToFloat(int bits)
Description:
Returns the single-float corresponding to a given bit representation. The argument is considered to be a
representation of a floating-point value according to the IEEE 754 floating-point “single precision” bit
layout.
If the argument is 0x7f800000, the result is positive infinity.
If the argument is 0xff800000, the result is negative infinity.
If the argument is any value in the range 0x7f800001 through 0x7fffffff or in the range
0xff800001 through 0xffffffff, the result is NaN. All IEEE 754 NaN values of type float are, in
effect, lumped together by the Java programming language into a single float value called NaN.
In all other cases, let s, e, and m be three values that can be computed from the argument:
int s = ((bits >> 31) == 0) ? 1 : -1;
int e = ((bits >> 23) & 0xff);
int m = (e == 0) ?
(bits & 0x7fffff) << 1 :
(bits & 0x7fffff) | 0x800000;
Then the floating-point result equals the value of the mathematical expression s&#183;m&#183;2e-150.

Parameters:
bits - an integer.
Returns: the single-format floating-point value with the same bit pattern.