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FFmpeg cheat sheet

A list of useful commands for the ffmpeg command line tool.

Download FFmpeg: https://www.ffmpeg.org/download.html

Full documentation: https://www.ffmpeg.org/ffmpeg.html

Basic conversion

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r = []
for i in range(1, 6):
    for j in range(7, 9):
        r.append((i, j))
print(r)
print(list((i, j) for i in range(1, 6) for j in range(7,9)))

# [(1, 7), (1, 8), (2, 7), (2, 8), (3, 7), (3, 8), (4, 7), (4, 8), (5, 7), (5, 8)]
# [(1, 7), (1, 8), (2, 7), (2, 8), (3, 7), (3, 8), (4, 7), (4, 8), (5, 7), (5, 8)]

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# sample example using plotly to plot emojis

import plotly.express as px
import pandas as pd

d = {"1": ["😀", "🥰", "😗"],
      "2": [1,2,3]
      }

px.scatter(pd.DataFrame(d), x="1", y="2")

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convert ipynb to md

jupyter nbconvert --to markdown /path/to/example_notebook.ipynb

append md to post.md

cat example_notebook.md | tee -a exampleblog/_posts/YYYY-MM-DD-example-post.md

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# https://www.geeksforgeeks.org/python-set-operations-union-intersection-difference-symmetric-difference/
A = {0, 2, 4, 6, 8} 
B = {1, 2, 3, 4, 5}
  
# union 
print("Union :", A | B) 
  
# intersection 
print("Intersection :", A & B) 
  

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def LIS(a):
    """Longest Increasing Subsequences"""
    L = [1] * len(a)
    for i in range(len(a)):
        for j in range(i):
            if a[j] < a[i] and L[i] < 1+L[j]:
                L[i] = 1 + L[j]
    return max(L)
a = [5,7,4,-3,9,1,10,4,5,8,9,3]
LIS(a)

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def fibM(n, d={0: 0, 1: 1}):
    """Memoization Fib"""
    if n-2 in d and n-1 in d:
        return d[n-2] + d[n-1]
    else:
        d[n-1] = d[n-3] + d[n-2]
        return fibM(n-1, d)
fib(25)

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def fibD(n):
    """DP Fib"""
    f = [0, 1]
    for i in range(2, n+1):
        f.append(f[i-2]+f[i-1])
    return f[n]
fib(25)

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def fibR(n):
    """recursive fib"""
    if n == 0:
        return 0
    if n == 1:
        return 1
    return fibR(n-1) + fibR(n-2)
fibR(25)

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sudo apt-get update

sudo apt-get -y install binutils

git clone https://github.com/aws/efs-utils

cd efs-utils

./build-deb.sh