Python

Useful techniques

Environment Variables

print(os.environ['HOME_ADDR']) # get
os.environ['HOME_ADDR']='xyz' # set

Global Variables

global x # use global inside functions to avoid getting a local variable

JSON Parsing

Reading and Writing JSON to a File in Python (stackabuse.com)

Language Syntax

isApple = True if fruit == 'Apple' else False # One liner if statements

myNewList = [[a,b] for a,b in mainList if a in secondaryList] # Array manipulation based on cond.

list_1 = [['good',100, 20, 0.2],['bad', 10, 0, 0.0],['change', 1, 2, 2]]
list_1 = [item for item in list_1 if item[2] >= 5 or item[3] >= 0.3]

Program Argument Handling

python - How to read/process command line arguments? - Stack Overflow

Saving Variables to Files

sample_list = [1, 2, 3]
file_name = "sample.pkl"

open_file = open(file_name, "wb")
pickle.dump(sample_list, open_file)
open_file.close()

open_file = open(file_name, "rb")
loaded_list = pickle.load(open_file)
open_file.close()

print(loaded_list)

Converting a List to String

strlist = ' '.join(map(str, list))