[Python] Basic syntax

• range()

>>> range(10)
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
>>> range(5,10)
[5, 6, 7, 8, 9]
>>> list(range(0,10,3))
[0, 3, 6, 9]

>>> list(range(10,0,-3))

[10, 7, 4, 1]

range(stop)                0 ≦ i < stop

range(start, stop)          start ≦ i < stop

range(start, stop, step)  start ≦ i < stop

range(stop, start, -step)  stop ≧ i > start

• for()

>>> names = ['pico', 'ted', 'hop']

>>> for i in names:

...      print i

pico

ted

hop

• remove(), del()

>>> names = ['pico', 'ted', 'hop']

>>> names.remove('pico')

>>> names

['ted', 'hop']

>>> names.pop(1)

'hop'

>>> names

['ted']

• random(), uniform(), randrange(), randint()

>>> num = range(5)

>>> num

[0, 1, 2, 3, 4]

>>> random.randint(0, len(nums)-1)

4

[Python] random function

import random

names = ['apple', 'orenge', 'banana', 'pineapple', 'lemon']

random_number = random.randint(0,len(names)-1)
chosen_one    = names[random_number]
print(chosen_one)

[Python] rename script in Linux

import glob, os, re

first_num = 1

files = sorted(glob.glob("*.exr"))
num = lambda files : int(re.sub("\\D", "", files))

files_sort = sorted(files, key=num)
#print(files_sort)

for i, old_name in enumerate(files_sort):
old_name_lib = old_name.split('.')
new_name1 = old_name_lib[0] + "." + old_name_lib[1] + "."
new_name2 = "{0:04d}.exr".format(i + first_num)

    os.rename(old_name,  new_name1 + new_name2)
    print(old_name + " = " + new_name1 + new_name2)

[Python] String Services

Pythonで文字列を置換（replace, translate, re.sub, re.subn）
https://note.nkmk.me/python-str-replace-translate-re-sub/
Python で ¥ (円マーク)を直接指定して置換するには
http://yoshidabenjiro.hatenablog.com/entry/2016/12/24/232150
ascii code backslash
https://theasciicode.com.ar/ascii-printable-characters/backslash-reverse-slash-ascii-code-92.html

[Python] for loop

# Prints out the numbers 2,3,5,7

primes = [2, 3, 5, 7]
for prime in primes:
    print(prime)

# Prints out the numbers 0,1,2,3,4
for x in range(5):
    print(x)

# Prints out 3,4,5
for x in range(3, 6):
    print(x)

# Prints out 3,5,7
for x in range(3, 8, 2):
    print(x)

# Prints out 0,1,2,3,4
count = 0
while count < 5:
    print(count)
    count += 1  # This is the same as count = count + 1

[Python] character string

-split function
https://www.pythonforbeginners.com/dictionary/python-split

-convert  int to strings
str(value)