Math 781: Matrices and Data

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Complex Numbers

In sage, the variables i and I can be used interchangably as the "imaginary unit".

The commands z.real() and z.imag() calculate the real and imaginary parts of z. The commands z.conjugate() and z.abs() calculate the conjugate and absolute value of z. We can calculate the recriprocal of z with 1/z.

Of course, we can add and multiply complex numbers with the syntax z1+z2 and z1*z2.

We can use the expected syntax to define a complex matrix A and a complex vector v. The syntax A*v calculates the associated matrix-vector product. The conjugate-transpose of A is given by A.H.

The inner product of two complex vectors is given by v1.hermitian_inner_product(v2).