For example:

z = r*(cosθ + i sinθ)

R is the modulus of z, that is, r = | z |

θ is the radial angle of z, which is denoted as θ = arg(z).

The radial angle of any non-zero complex number z=a+bi has an infinite number of values, which are different by integer multiples of 2π. Applicable to-π

For a more general case, such as z = x+iy, it can be regarded as a plane vector. If its real part and imaginary part are regarded as horizontal and vertical components in a rectangular coordinate system, then Arg z = arctan(y/x).

Extended data:

Complex algorithm

Addition rule

The addition rule of complex numbers: let z 1=a+bi and z2=c+di be any two complex numbers. The real part of sum is the sum of the original two complex real parts, and its imaginary part is the sum of the original two imaginary parts. The sum of two complex numbers or a complex number. ?

Multiplication rule

Complex multiplication rule: two complex numbers are multiplied, similar to two polynomials. In the result, i2=-1, and the real part and imaginary part are merged respectively. The product of two complex numbers is still a complex number.

References:

Baidu encyclopedia -arg