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Version: 4.16

Q5

Defines a "floating point number" with 5 bits reserved for the fractional part of the decimal number. Q5 implements some simple arithmetic operations, most yielding a Q5 number and some yielding a Q10 number as a result. Other operations also work with Q15 numbers.

See: Q10, Q15

Public Functions#

intceil() const
Convert the Q5 value to an integer by removing the 5 bits used for the fraction.
operator int() const
Gets the Q5 as an integer without conversion.
Q5operator*(const int i) const
Multiplication operator.
Q5operator*(const Q15 & q15) const
Multiplication operator.
Q10operator*(const Q5 & q5) const
Multiplication operator.
Q5operator+(const Q5 & q5) const
Addition operator.
Q5operator-() const
Negation operator.
Q5operator-(const Q5 & q5) const
Subtraction operator.
Q5operator/(const int i) const
Division operator.
Q5operator/(const Q5 q5) const
Division operator.
Q5()
Initializes a new instance of the Q5 class.
Q5(const Q10 q10)
Constructor from Q10.
Q5(int i)
Constructor from integer.
intround() const
Round the Q5 value to the nearest integer value.
template \<typename T \>
T
to() const
Convert the Q5 value to an integer by removing the 5 bits used for the fraction, or to a floating point value by dividing by 32, depending on the type specified as T.

Public Functions Documentation#

ceil#

int ceil()const

Convert the Q5 value to an integer by removing the 5 bits used for the fraction.

The number is rounded up to the nearest integer.

Returns:

The first integer value higher than (or equal to) the Q5 value.

operator int#

Gets the Q5 as an integer without conversion.

Returns:

The unconverted Q5 value.

operator*#

Q5 operator*(const inti)

Multiplication operator.

Parameters:
iThe integer to multiply this with.
Returns:

The result of the operation.

operator*#

Q5 operator*(const Q15 &q15)

Multiplication operator.

Often used in relation with sine and cosine calculation which are pre-calculated as Q15. As the result is needed as a Q5, this operator multiplies with the given Q15 and converts the result to a Q5.

Parameters:
q15The Q15 to multiply this with.
Returns:

The result of the operation.

See also:

operator*#

Q10 operator*(const Q5 &q5)

Multiplication operator.

The result is a Q10, not a Q5, for increased precision.

Parameters:
q5The Q5 to multiply this with.
Returns:

The result of the operation.

See also:

operator+#

Q5 operator+(const Q5 &q5)

Addition operator.

Parameters:
q5The Q5 to add to this.
Returns:

The result of the operation.

operator-#

Q5 operator-()const

Negation operator.

Returns:

The negative value of this.

operator-#

Q5 operator-(const Q5 &q5)

Subtraction operator.

Parameters:
q5The Q5 to subtract from this.
Returns:

The result of the operation.

operator/#

Q5 operator/(const inti)

Division operator.

Parameters:
iThe integer to divide this by.
Returns:

The result of the operation.

operator/#

Q5 operator/(const Q5q5)

Division operator.

Internally this Q5 is converted to Q10 before the division to increased precision.

Parameters:
q5The Q5 to divide this by.
Returns:

The result of the operation.

See also:

Q5#

Q5()

Initializes a new instance of the Q5 class.

Q5#

Q5(const Q10q10)

Constructor from Q10.

The Q10 is shifted down to convert it to Q5, thus the value is rounded down in the conversion.

Parameters:
q10The Q10 value to convert to a Q5 value.
See also:

Q5#

explicit Q5(inti)

Constructor from integer.

No conversion is done - the integer is assumed to already be in Q5 format.

Parameters:
iInteger pre-formattet in Q5 format.

round#

int round()const

Round the Q5 value to the nearest integer value.

Returns:

The integer closest to the Q5 value.

to#

to()const

Convert the Q5 value to an integer by removing the 5 bits used for the fraction, or to a floating point value by dividing by 32, depending on the type specified as T.

Template Parameters:
TEither int or float.
Returns:

Q5 value as a type T.

Note

Using "to<int16_t>()" result in loss of precision. Use "(int16_t)to<int>()" instead.