How to plot a complex number in python using matplotlib ?

An example of how to plot a complex number in python using matplotlib:

Plot a complex number

Let's consider the following complex number

z1 = 4 + 2i

Example of how to create a python function to plot a geometric representation of a complex number:

import matplotlib.pyplot as plt
import numpy as np
import math

z1 = 4.0 + 2.*1j

x_min = -5.0
x_max = 5.0

y_min = -5.0
y_max = 5.0

def plot_complex_number_geometric_representation(z,x_min,x_max,y_min,y_max):

    fig = plt.figure()

    ax = plt.gca()

    ax.spines['left'].set_position('zero')
    ax.spines['right'].set_color('none')
    ax.spines['bottom'].set_position('zero')
    ax.spines['top'].set_color('none')

    a = [0.0,0.0]
    b = [z.real,z.imag]

    head_length = 0.2

    dx = b[0] - a[0]
    dy = b[1] - a[1]

    vec_ab = [dx,dy]

    vec_ab_magnitude = math.sqrt(dx**2+dy**2)

    dx = dx / vec_ab_magnitude
    dy = dy / vec_ab_magnitude

    vec_ab_magnitude = vec_ab_magnitude - head_length

    ax = plt.axes()

    ax.arrow(a[0], a[1], vec_ab_magnitude*dx, vec_ab_magnitude*dy, head_width=head_length, head_length=head_length, fc='black', ec='black')

    plt.scatter(a[0],a[1],color='black',s=2)
    plt.scatter(b[0],b[1],color='black',s=2)

    #ax.annotate('A', (a[0]-0.4,a[1]),fontsize=14)
    ax.annotate('z1', (b[0]+0.3,b[1]),fontsize=10)


    ax.text(0, y_max+0.5, r'Img', fontsize=10, horizontalalignment='center')
    ax.text(x_max+0.5, 0, r'Real', fontsize=10, verticalalignment='center')

    plt.xlim(x_min,x_max)
    plt.ylim(y_min,y_max)

    plt.grid(True,linestyle='--')

    plt.savefig('plot_complex_number_geometric_representation_01.png', bbox_inches='tight')
    #plt.show()
    plt.close()


plot_complex_number_geometric_representation(z1,x_min,x_max,y_min,y_max)

References