sin

Use the sin function in APL to compute the sine of an angle expressed in radians. The function accepts any real number and returns a value in the range [-1, 1].

sin is most commonly used in observability to encode time-of-day or other periodic signals as cyclic coordinates. When combined with cos, it produces a two-dimensional representation of periodic phenomena that preserves circular distance. For example, you can encode hour-of-day cyclically so that hour 23 and hour 0 are treated as adjacent.

Usage

Syntax

sin(x)

Parameters

Returns

The sine of x, a real number in the range [-1, 1].

Example

Use sin to compute the sine of an angle in radians.

Query

print result = sin(pi() / 2)

Output

List of related functions

• cos: Returns the cosine. Use sin and cos together to produce a two-dimensional cyclic encoding of angles.
• tan: Returns the tangent. Use it when you need the ratio of sine to cosine.
• asin: Returns the arc sine. Use it as the inverse of sin.
• pi: Returns the constant π. Use it to construct radian values before calling sin.
• radians: Converts degrees to radians. Use it to prepare degree inputs before calling sin.

Other query languages