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Hello, python

0 likes • Jan 20, 2021 • 2 views
Python
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More Python Posts

print indices

0 likes • Nov 18, 2022 • 0 views
Python
# List
lst = [1, 2, 3, 'Alice', 'Alice']
# One-Liner
indices = [i for i in range(len(lst)) if lst[i]=='Alice']
# Result
print(indices)
# [3, 4]

Distinct Primes Finder > 1000

0 likes • Nov 18, 2022 • 3 views
Python
primes=[]
products=[]
def prime(num):
if num > 1:
for i in range(2,num):
if (num % i) == 0:
return False
else:
primes.append(num)
return True
for n in range(30,1000):
if len(primes) >= 20:
break;
else:
prime(n)
for previous, current in zip(primes[::2], primes[1::2]):
products.append(previous * current)
print (products)

combine values

0 likes • Nov 19, 2022 • 0 views
Python
from collections import defaultdict
def combine_values(*dicts):
res = defaultdict(list)
for d in dicts:
for key in d:
res[key].append(d[key])
return dict(res)
d1 = {'a': 1, 'b': 'foo', 'c': 400}
d2 = {'a': 3, 'b': 200, 'd': 400}
combine_values(d1, d2) # {'a': [1, 3], 'b': ['foo', 200], 'c': [400], 'd': [400]}

Dictionary Sort

0 likes • Nov 18, 2022 • 0 views
Python
mydict = {'carl':40, 'alan':2, 'bob':1, 'danny':0}
# How to sort a dict by value Python 3>
sort = {key:value for key, value in sorted(mydict.items(), key=lambda kv: (kv[1], kv[0]))}
print(sort)
# How to sort a dict by key Python 3>
sort = {key:mydict[key] for key in sorted(mydict.keys())}
print(sort)

screencap.py

0 likes • Jan 23, 2021 • 0 views
Python
"""
Take screenshots at x interval - make a movie of doings on a computer.
"""
import time
from datetime import datetime
import ffmpeg
import pyautogui
while True:
epoch_time = int(time.time())
today = datetime.now().strftime("%Y_%m_%d")
filename = str(epoch_time) + ".png"
print("taking screenshot: {0}".format(filename))
myScreenshot = pyautogui.screenshot()
myScreenshot.save(today + "/" + filename)
time.sleep(5)
#
# and then tie it together with: https://github.com/kkroening/ffmpeg-python/blob/master/examples/README.md#assemble-video-from-sequence-of-frames
#
"""
import ffmpeg
(
ffmpeg
.input('./2021_01_22/*.png', pattern_type='glob', framerate=25)
.filter('deflicker', mode='pm', size=10)
.filter('scale', size='hd1080', force_original_aspect_ratio='increase')
.output('movie.mp4', crf=20, preset='slower', movflags='faststart', pix_fmt='yuv420p')
.run()
)
"""

Radix sort

0 likes • Nov 19, 2022 • 1 view
Python
# Python program for implementation of Radix Sort
# A function to do counting sort of arr[] according to
# the digit represented by exp.
def countingSort(arr, exp1):
n = len(arr)
# The output array elements that will have sorted arr
output = [0] * (n)
# initialize count array as 0
count = [0] * (10)
# Store count of occurrences in count[]
for i in range(0, n):
index = (arr[i]/exp1)
count[int((index)%10)] += 1
# Change count[i] so that count[i] now contains actual
# position of this digit in output array
for i in range(1,10):
count[i] += count[i-1]
# Build the output array
i = n-1
while i>=0:
index = (arr[i]/exp1)
output[ count[ int((index)%10) ] - 1] = arr[i]
count[int((index)%10)] -= 1
i -= 1
# Copying the output array to arr[],
# so that arr now contains sorted numbers
i = 0
for i in range(0,len(arr)):
arr[i] = output[i]
# Method to do Radix Sort
def radixSort(arr):
# Find the maximum number to know number of digits
max1 = max(arr)
# Do counting sort for every digit. Note that instead
# of passing digit number, exp is passed. exp is 10^i
# where i is current digit number
exp = 1
while max1/exp > 0:
countingSort(arr,exp)
exp *= 10
# Driver code to test above
arr = [ 170, 45, 75, 90, 802, 24, 2, 66]
radixSort(arr)
for i in range(len(arr)):
print(arr[i]),