While循环，有/无输入（Python）

Question

我正在构建一个脚本来绘制平滑和绘制值。但是，我无法使用yes/no函数来控制while循环。

我将while条件设置为“N”，并等待用户在退出之前说他们喜欢绘图（输入Y）。

我收到一个“NameError:name'reply'未定义。”

import matplotlib.pyplot as plt
import numpy

while True:
    reply[0] = 'n'
    def yes_or_no(question):
        reply = str(input(question+' (y/n): ')).lower().strip()
        if reply[0] == 'y':
            return 1
        if reply[0] == 'n':
            return 0
        else:
            return yes_or_no("Please Enter (y/n) ")

# a bunch of math
# plots for the user

yes_or_no('Do you like the plot')
break
print("done")

当我调整回复[0]以回复程序挂起时（见下文）

print("started")
while True:
    reply = 'n'
    def yes_or_no(question):
        reply = str(input(question+' (y/n): ')).lower().strip()
        if reply[0] == 'y':
            return 1
        if reply[0] == 'n':
            return 0
        else:
            return yes_or_no("Please Enter (y/n) ")

yes_or_no('Do you like the plot')
print("done")

Answer 1

尝试：

def yes_or_no(question):
    reply = str(input(question+' (y/n): ')).lower().strip()
    if reply[0] == 'y':
        return 1
    elif reply[0] == 'n':
        return 0
    else:
        return yes_or_no("Please Enter (y/n) ")

print("started")
while True:
    # DRAW PLOT HERE;
    print("See plot....")
    if(yes_or_no('Do you like the plot')):
        break
print("done")

为了清晰起见，最好将函数定义与循环分开。另外，否则它将在每个循环中被读取，浪费资源。

输出：

$ python ynquestion.py 
started
See plot....
Do you like the plot (y/n): n
See plot....
Do you like the plot (y/n): N 
See plot....
Do you like the plot (y/n): NO
See plot....
Do you like the plot (y/n): No
See plot....
Do you like the plot (y/n): no
See plot....
Do you like the plot (y/n): yes
done
$