Scope: Global vs. Local

Left , Right Alignment, String Formatting


from decimal import *

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[: : -1]

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*args , **kwargs

Anonymous Function:
List & Lambda
list1 = [lambda x: x**2, lambda x: x**3, lambda x:x**4]
for f in list1:
print(type(f))
print(f(3))
print('--------')
Output:
<class 'function'> 9 -------- <class 'function'> 27 -------- <class 'function'> 81 --------
Dictionary & Lambda
Example:
dict.get(key[, value])
get() Parameters
The get() method takes maximum of two parameters:
key - key to be searched in the dictionary
value (optional) - Value to be returned if the key is not found. The default value is None.

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Map & Filter


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import random
import math


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file = open('file_name', 'w', encoding = 'utf-8')
file.write(text) # text has to be string
file.close()
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How to read file?

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line.strip()
remove leading and trailing spaces


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import csv
csv.reader(file) => if the data doesn't contain header/title

csv.DictReader(file) => if the data contain header/title

csv.writer()

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json.dump() ; json.dumps() => Python to Json file

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json.load() ; json.loads() => Json to Python file

try; except

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import os


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import numpy as np
np.array()

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# ndarray.ndim
# ndarray.shape
# ndarray.size
# ndarray.dtype

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np.empty() ; np.ones() ; np.full() ; np.eye() ; np.diag()


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np.arange() ; (decimals are allowed )
np.arange().reshape()
np.linspace(); (default number is 50, default endpoint will be included)

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How to filter np.array() ?

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Extract values, update values from array

Extract values with list, tuple

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Difference between resize and reshape
resize: creates new array
reshape: modifies the original array


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np.reciprocal() ; np.round(value, decimal = n)

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