## 2018年1月24日水曜日

### Python - Numbers and Variables: Python Does the Math(CIRCULAR SPIRALS, turtle module, numinput method)

Teach Your Kids to Code: A Parent-Friendly Guide to Python Programming (Bryson Payne(著)、No Starch Press)のChapter 3.(Numbers and Variables: Python Does the Math)、PROGRAMMING CHALLENGES、#1: CIRCULAR SPIRALSを取り組んでみる。

#1: CIRCULAR SPIRALS

コード(Emacs)

Python 3

```#!/usr/bin/env python3
import turtle
import time

t = turtle.Pen()
t.speed(0)
turtle.bgcolor('black')
colors = ['red', 'yellow', 'blue', 'orange',
'green', 'purple', 'brown', 'white', 'gray', 'pink']
sides = int(turtle.numinput('Number of sides',
'How many sides do you want(1-8)?', 4, 1, 8))
for x in range(100):
t.pencolor(colors[x % sides])
t.circle(x)
t.forward(x * 3 / sides + x)
t.left(360 / sides + 1)
t.width(x * sides / 200)
print('done')
while True:
time.sleep(10)
```

```\$ ./sample1.py
done
C-c C-cTraceback (most recent call last):
File "./sample1.py", line 20, in <module>
time.sleep(10)
KeyboardInterrupt
\$ ./sample1.py
done
C-c C-cTraceback (most recent call last):
File "./sample1.py", line 20, in <module>
time.sleep(10)
KeyboardInterrupt
\$ ./sample1.py
done
C-c C-cTraceback (most recent call last):
File "./sample1.py", line 20, in <module>
time.sleep(10)
KeyboardInterrupt
\$
```