Visdom draws multiple dynamic loss curves

from visdom import Visdom
from  time import sleep


'''

 Take these three curves as an example ：
y = 80*x
y = x**2
y = -100*x-100

'''

viz = Visdom()
x = []
Yn =[]

opts1 = {
    "title": 'chart example1',
    "xlabel":'x',
    "ylabel":'y',
    "width":500,
    "height":300,
    "legend":['b','c','d']
}
opts2 = {
    "title": 'chart example2',
    "xlabel":'x',
    "ylabel":'y',
    "width":500,
    "height":300,
    "legend":['b','c','d']
}
for i in range(1000):
    x.append(i)
    Yn.append([i*80, i**2, -i*100-100])

    ## Mode one ,replace
    viz.line(X=x, Y=Yn, win='chart1',env='dynamic', opts=opts1)

    ## Mode two ,append
    viz.line(X=[i], Y=[[i * 80, i ** 2, -i * 100 - 100]], win='chart2', env='dynamic',update='append',
             opts=opts2)
    sleep(0.01)