cos

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The cosine of the argument is in radians.

Library

EngeeDSP

Syntax

Y = cos(X) — returns the cosine value for each element from X. Function cos works with arrays piecemeal. The function accepts both real and complex inputs.
- For real values from X, function cos returns real values in the interval [-1, 1].
- For complex values from X, function cos returns complex values.

# X is the value of the input angle in rad

+ scalar | vector | matrix | N-dimensional array

Details

The value of the input angle in rad, specified as a scalar, vector, matrix, or multidimensional array.

Data types	`Float32`, `Float64`, `Char`, `String`
Support for complex numbers	Yes

# Y is the cosine value of the input angle

+ scalar | vector | matrix | N-dimensional array

Details

The cosine value of the input angle returned as a real or complex scalar, vector, matrix, or multidimensional array.

Data types	`Float32`, `Float64`, `Char`, `String`
Support for complex numbers	Yes

Details

Let’s plot the cosine function for .

import EngeeDSP.Functions: cos
using Plots

x = -pi:0.01:pi
plot(x, cos.(x), grid = true)
xlabel!("x")
ylabel!("cos(x)")

cos 2

Details

Calculate the cosine of the complex angles of the vector .

import EngeeDSP.Functions: cos

x = [-im, pi + im*pi/2, -1 + im*4]
y = cos.(x)

3-element Vector{ComplexF64}:
  1.5430806348152437 + 0.0im
 -2.5091784786580567 - 2.818278334591946e-16im
  14.754701170483758 + 22.96367349919304im

Details

Cosine of the angle a right triangle is equal to:

Where

sin en

The cosine of a complex quantity equal to: