Python: Difference between revisions
Line 41: | Line 41: | ||
with open('your_file.txt', 'w') as f: | with open('your_file.txt', 'w') as f: | ||
f.write("\n".join(my_list)) | f.write("\n".join(my_list)) | ||
</syntaxhighlight> | |||
====Create Directory if it doesn't exist==== | |||
[https://stackoverflow.com/questions/12517451/automatically-creating-directories-with-file-output Reference] | |||
<syntaxhighlight lang="python"> | |||
def ensure_dir_exists(filename): | |||
if not os.path.exists(os.path.dirname(filename)): | |||
try: | |||
os.makedirs(os.path.dirname(filename)) | |||
except OSError as exc: # Guard against race condition | |||
if exc.errno != errno.EEXIST: | |||
raise | |||
</syntaxhighlight> | </syntaxhighlight> | ||
Revision as of 12:16, 10 October 2019
Installation
Use Anaconda.
Basic Usage
How to use Python 3.
Ternary Operator
is_nice = True
state = "nice" if is_nice else "not nice"
Lambda Function
lambda x: x * 2
Filesystem Read and Write
List all files in a folder
gazeDir = "Gaze_txt_files"
# List of folders in root folder
gazeFolders = [path.join(gazeDir, x) for x in os.listdir(gazeDir)]
# List of files 2 folders down
gazeFiles = [path.join(x, y) for x in gazeFolders for y in os.listdir(x)]
Read/Write entire text file into a list
Reading
[1]
with open('C:/path/numbers.txt') as f:
lines = f.read().splitlines()
Writing
[2]
with open('your_file.txt', 'w') as f:
f.write("\n".join(my_list))
Create Directory if it doesn't exist
def ensure_dir_exists(filename):
if not os.path.exists(os.path.dirname(filename)):
try:
os.makedirs(os.path.dirname(filename))
except OSError as exc: # Guard against race condition
if exc.errno != errno.EEXIST:
raise
Regular Expressions (Regex)
import re
myReg = re.compile(r'height:(\d+)cm')
myMatch = re.match(myReg, "height:33cm");
print(myMatch[1])
# 33
Spawning Processes
Use subprocess to spawn other programs.
import subprocess
subprocess.run(["ls", "-l"], cwd="/")