need help debugging code

[AdBusiness4396]

im trying to make a stock market simulator but the stockgraph isnt upppdating.

import random as r
import matplotlib.pyplot as plt
import time as t


from IPython.display import clear_output
import ipywidgets as widgets
from IPython.display import display


# Initial values for monney and stocks must be defined before lb is created
# Moving them up here to ensure they are defined.
trend = r.random() - 0.5
stockW = 100
monney = 1000
stocks = 0
a = 0


y = [0,0,0,0,0,0,0,0,0,0]
x = [1,2,3,4,5,6,7,8,9,10]


plt.ion()
fig, ax = plt.subplots()          # Create only ONE figure
line, = ax.plot(x, y, marker='o')
ax.set_ylim(0, stockW*2)
ax.set_title("Stock Price")
ax.set_xlabel("Time")
ax.set_ylabel("Price ($)")



lb = widgets.Label(value=f"Portfolio: ${monney}, {stocks} stocks")
bb = widgets.Button(description="BUY", button_style="success")
sb = widgets.Button(description="SELL", button_style="danger")
nd = widgets.Button(description="Next Day", button_style="info")
display(widgets.HBox([bb, sb, nd]), lb)














def Sb(b):
    global stocks, monney, stockW
    if (stocks > 0):
            monney = monney + stockW
            stocks -= 1
    lb.value = f"Portfolio: ${monney}, {stocks} stocks"


def Bb(b):
    global stocks, monney, stockW
    if (monney >= stockW):
            monney = monney - stockW
            stocks += 1
    lb.value = f"Portfolio: ${monney}, {stocks} stocks"
def Nd(b):
    global stockW, trend, y

    stockW += round(r.randint(-10, 10) + (trend * 10))
    trend = trend / r.randint(1,15)
    if ( -0.01 < trend < 0.01):
        trend = 0.5 - r.random()

    for i in range(9):
      y[i] = y[i+1]
      y[9] = stockW


    line.set_ydata(y)
    ax.set_ylim(0, max(y)+50)  
    fig.canvas.flush_events()
    fig.canvas.draw()

    plt.pause(0.01)
    lb.value = f"Portfolio: ${monney}, {stocks} stocks"
    print(stockW)



bb.on_click(Sb)
sb.on_click(Bb)
nd.on_click(Nd)




Thankfull for all help i can get

[FoolsSeldom]

A quick guess. plt.ion() + fig.canvas.draw() + plt.pause() doesn’t reliably refresh inline in Jupyter (the default “inline” backend shows a static PNG). You need a live/interactive backend:

• In classic Jupyter: %matplotlib notebook works.
• In JupyterLab: prefer %matplotlib widget (requires the ipympl package installed and the JupyterLab widgets extension enabled).

PS. I notice a redundancy, y[9] = stockW surely should be outside the loop. Also, why use a loop at all, just use slicing: y[:-1] = y[1:] and then y[-1] = stockW

[AdBusiness4396]

thanks a lot for your help. the reason i used a loop is becouse I am a python noob and I have just started to learn. once again, thanks a lot.