Qt Reference Documentation

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# <QtCore/qmath.h> - Math Functions

The <QtCore/qmath.h> header provides various math functions. More...

## Functions

qreal | qAcos ( qreal v )
qreal | qAsin ( qreal v )
qreal | qAtan2 ( qreal y, qreal x )
qreal | qAtan ( qreal v )
int | qCeil ( qreal v )
qreal | qCos ( qreal v )
qreal | qExp ( qreal v )
int | qFloor ( qreal v )
qreal | qLn ( qreal v )
qreal | qPow ( qreal x, qreal y )
qreal | qSin ( qreal v )
qreal | qSqrt ( qreal v )
qreal | qTan ( qreal v )

## Function Documentation

### qreal qAcos ( qreal v )

Returns the arccosine of v as an angle in radians. Arccosine is the inverse operation of cosine.

See also qAtan(), qAsin(), and qCos().

### qreal qAsin ( qreal v )

Returns the arcsine of v as an angle in radians. Arcsine is the inverse operation of sine.

See also qSin(), qAtan(), and qAcos().

### qreal qAtan2 ( qreal y, qreal x )

Returns the arctangent of a point specified by the coordinates y and x. This function will return the angle (argument) of that point.

See also qAtan().

### qreal qAtan ( qreal v )

Returns the arctangent of v as an angle in radians. Arctangent is the inverse operation of tangent.

See also qTan(), qAcos(), and qAsin().

### int qCeil ( qreal v )

Return the ceiling of the value v.

The ceiling is the smallest integer that is not less than v. For example, if v is 41.2, then the ceiling is 42.

See also qFloor().

### qreal qCos ( qreal v )

Returns the cosine of an angle v in radians.

See also qSin() and qTan().

### qreal qExp ( qreal v )

Returns the exponential function of `e` to the power of v.

See also qLn().

### int qFloor ( qreal v )

Return the floor of the value v.

The floor is the largest integer that is not greater than v. For example, if v is 41.2, then the floor is 41.

See also qCeil().

### qreal qLn ( qreal v )

Returns the natural logarithm of v. Natural logarithm uses base e.

See also qExp().

### qreal qPow ( qreal x, qreal y )

Returns the value of x raised to the power of y. That is, x is the base and y is the exponent.

See also qSqrt().

### qreal qSin ( qreal v )

Returns the sine of the angle v in radians.

See also qCos() and qTan().

### qreal qSqrt ( qreal v )

Returns the square root of v. This function returns a NaN if v is a negative number.

See also qPow().

### qreal qTan ( qreal v )

Returns the tangent of an angle v in radians.

See also qSin() and qCos().