How to optimize this program? (Im a bit of a beginner)

Question

I'm trying to simulate Python (I'm a Physics student and programming is not my strongest skill) and I am running short of RAM. I have 4Gb only.

This is my python program:

#!/usr/bin/env python3
# -*- coding: utf-8 -*-
"""
Created on Tue May 11 21:10:00 2021

@author: samuel
"""

import numpy as np
import pandas as pd
import matplotlib.pyplot as plt

from funciones import *
from ctes import *

gif_1d = True
gif_2d = True

agents = [w]*N

path_graf='/home/samuel/Documents/FISICA/20-21/Física de los sistemas complejos/Proyecto/Programas/imagenes/grafico/'
path_map = '/home/samuel/Documents/FISICA/20-21/Física de los sistemas complejos/Proyecto/Programas/imagenes/mapa/'


#Dimension del mapa 2d
dim = int(np.sqrt(N))

for i in range(iterations):
    #tomar dos al azar
    ag1, ag2 = eleccion_agentes()
    
    #se realiza la transaccion
    agents[ag1],agents[ag2] = transaccion(agents[ag1],agents[ag2])
    
    #cada 100 iteraciones se guarda una imagen para el gif
    if i%5000==0:
        if gif_1d:
             fig,ax = plt.subplots(figsize=(15,10))
             ax.bar(range(1,N+1),agents)
             ax.set_ylabel('Riqueza')
             ax.set_title('Iteracion:' + str(i))
             frame = f'{i}.png'    
             plt.savefig(path_graf + frame)
             plt.close()
             
        if gif_2d:
            fig,ax = plt.subplots(figsize=(15,10))
            mapa= np.reshape(np.array(agents),(dim,dim))
            ax.imshow(mapa, cmap='viridis', interpolation='nearest')
            ax.set_title('Iteracion:' + str(i))
            frame = f'{i}.png'    
            plt.savefig(path_map + frame)
            plt.close()

The modules funciones.py and ctes.py are, respectively

#!/usr/bin/env python3
# -*- coding: utf-8 -*-
"""
Created on Wed May 12 19:56:51 2021

@author: samuel
"""
from ctes import *
import random

def eleccion_agentes():
    iguales=True
    while iguales:
        x1=random.randint(0,N-1)
        x2=random.randint(0,N-1)
        if x1!=x2:
            iguales=False
    return x1, x2

#función que dados dos agentes, hace la transaccion y devuelve las nuevas riquezas
#de los mismos
def transaccion(w1,w2):
    delta=random.uniform(0.0,alfa)*min(w1,w2)
    if random.random() <= 0.5:
        w1=w1+delta
        w2=w2-delta
    else:
        w1=w1-delta
        w2=w2+delta
    
    return w1,w2

and

#!/usr/bin/env python3
# -*- coding: utf-8 -*-
"""
Created on Wed May 12 19:57:28 2021

@author: samuel
"""

iterations = int(5e7)    #iterations for the simulation (number of transactions)


N=10000      #total number of agents (but we can work with the normalized distrib: N=1 and W=1)
            #DEBE SER NUMERO CON RAIZ, PARA QUE EL GIF 2D SALGA BIEN.
            
w = 100         #units of initial wealth for each agent.
W = w*N         #total wealth

alfa = 0.25     #

As said, the problem is that I run out of RAM. Before, when I tried to create the gif in the same problem, the images were being saved on a list as they were created (every 5000 iterations) but now I'm just saving them in some directory to make the animation after. I thought this would improve the use of RAM since there is no big variable increasing with each iteration. But I still fill my memory.

What could I do for this not to happen?

PD: I'm using the Spyder environment if that's of any use.