29Oct/20

Python + Guitar + All Notes

2020-10-29Music, Programmingkossboss

I came across this medium article about python and guitar strings and plotting scales. It has an interesting Jupyter notebook to work with, allowing to plot scales for all of the chords.Read More…

23Oct/20

Python remove duplicates similar to bash uniq + sort

2020-10-23Linux, Programmingkossboss

# citing: https://www.reddit.com/r/Python/comments/jfx7wy/how_to_quickly_remove_duplicates_from_a_list/

# Let's make some duplicates (one million numbers between 1 and 100)

from random import randrange
DUPLICATES = [ randrange(100) for _ in range(1_000_000) ]

### METHOD 1 ### 

# Not very efficient - Similar to "sort | uniq" but the original order is kept

unique = []
for element in DUPLICATES:
    if element not in unique:
        unique.append(element)
print(unique)

# Output:
[95, 62, 73, 27, 89, 88, 31, 50, 26, 97, 13, 18, 54, 64, 17, 94, 72, 65, 83, 14, 40, 91, 1, 21, 22, 52, 61, 15, 7, 80, 24, 42, 37, 96, 74, 9, 59, 44, 66, 20, 6, 84, 39, 81, 2, 67, 32, 77, 36, 5, 8, 47, 55, 82, 60, 35, 33, 75, 57, 68, 29, 11, 23, 86, 69, 99, 25, 78, 76, 19, 12, 92, 10, 90, 16, 3, 51, 4, 28, 0, 71, 46, 79, 85, 58, 48, 93, 56, 53, 98, 87, 30, 45, 63, 70, 38, 41, 43, 34, 49]

### METHOD 2 ###

# Very efficient - Similar to "sort | uniq"

list(set(DUPLICATES))

# This works because sets contain unique items by definition

# Output:
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99]

### METHOD 3 ###

# Very efficient but order preserved
# Not sure which bash function this is similar to
# Resembles "sort | uniq" but with the original order preserved
# But sets are unordered! What if we need to preserve the order?
# Use this dict.fromkeys() trick!
list(dict.fromkeys(DUPLICATES))

# Output:
[95, 62, 73, 27, 89, 88, 31, 50, 26, 97, 13, 18, 54, 64, 17, 94, 72, 65, 83, 14, 40, 91, 1, 21, 22, 52, 61, 15, 7, 80, 24, 42, 37, 96, 74, 9, 59, 44, 66, 20, 6, 84, 39, 81, 2, 67, 32, 77, 36, 5, 8, 47, 55, 82, 60, 35, 33, 75, 57, 68, 29, 11, 23, 86, 69, 99, 25, 78, 76, 19, 12, 92, 10, 90, 16, 3, 51, 4, 28, 0, 71, 46, 79, 85, 58, 48, 93, 56, 53, 98, 87, 30, 45, 63, 70, 38, 41, 43, 34, 49]

### METHOD 4 ###

# Older Python - Similar to "uniq | sort"
# But it only works for Python 3.6 and above
# For Python 2.7 and 3.0-3.5, use OrderedDict:from collections import OrderedDict
list(OrderedDict.fromkeys(DUPLICATES))

#### METHOD 5 ###

# Crunch duplicates as they appear and show count
# Similar to bashes "uniq -c"
# I will show you how to do "uniq -c" on a string
# Just change the input to a list and it will work on a list

# METHOD 5.1 #

from itertools import groupby
input = "Raaanndommmm Leetters"
for i,v in groupby(input):
   print(len(list(v)),i)

# Output:
1 R
3 a
2 n
1 d
1 o
4 m
1
1 L
2 e
2 t
1 e
1 r
1 s

# METHOD 5.2 #

# Or you can return a list for an output:

l=[]
for i,v in groupby(input):
   l.append(str(len(list(v)))+" "+str(i))
print(l)

# Output:
['1 R', '3 a', '2 n', '1 d', '1 o', '4 m', '1  ', '1 L', '2 e', '2 t', '1 e', '1 r', '1 s']

#  METHOD 5.3 #

# Same solution as a one liner:

print([ str(len(list(v)))+" "+str(i) for i,v in groupby(input)])

# Output:
['1 R', '3 a', '2 n', '1 d', '1 o', '4 m', '1  ', '1 L', '2 e', '2 t', '1 e', '1 r', '1 s']

### METHOD 6 ###

# Crunch out duplicates but dont show count

# METHOD 6.1 #

from itertools import groupby
input = "Raaanndommmm Leetters"
for i,v in groupby(input):
   print(str(i))

# Output:
R
a
n
d
o
m

L
e
t
e
r
s

# METHOD 6.2 #

l=[]
for i,v in groupby(input):
   l.append(str(i))
print(l)

# Output:
['R', 'a', 'n', 'd', 'o', 'm', ' ', 'L', 'e', 't', 'e', 'r', 's']

# METHOD 6.3 #

print([ str(i) for i,v in groupby(input)])
# Output:

['R', 'a', 'n', 'd', 'o', 'm', ' ', 'L', 'e', 't', 'e', 'r', 's']

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# citing: https://www.reddit.com/r/Python/comments/jfx7wy/how_to_quickly_remove_duplicates_from_a_list/

# Let's make some duplicates (one million numbers between 1 and 100)

from random import randrange

DUPLICATES = [ randrange(100) for _ in range(1_000_000) ]

### METHOD 1 ###

# Not very efficient - Similar to "sort | uniq" but the original order is kept

unique = []

for element in DUPLICATES:

if element not in unique:

unique.append(element)

print(unique)

# Output:

[95, 62, 73, 27, 89, 88, 31, 50, 26, 97, 13, 18, 54, 64, 17, 94, 72, 65, 83, 14, 40, 91, 1, 21, 22, 52, 61, 15, 7, 80, 24, 42, 37, 96, 74, 9, 59, 44, 66, 20, 6, 84, 39, 81, 2, 67, 32, 77, 36, 5, 8, 47, 55, 82, 60, 35, 33, 75, 57, 68, 29, 11, 23, 86, 69, 99, 25, 78, 76, 19, 12, 92, 10, 90, 16, 3, 51, 4, 28, 0, 71, 46, 79, 85, 58, 48, 93, 56, 53, 98, 87, 30, 45, 63, 70, 38, 41, 43, 34, 49]

### METHOD 2 ###

# Very efficient - Similar to "sort | uniq"

list(set(DUPLICATES))

# This works because sets contain unique items by definition

# Output:

[0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99]

### METHOD 3 ###

# Very efficient but order preserved

# Not sure which bash function this is similar to

# Resembles "sort | uniq" but with the original order preserved

# But sets are unordered! What if we need to preserve the order?

# Use this dict.fromkeys() trick!

list(dict.fromkeys(DUPLICATES))

# Output:

### METHOD 4 ###

# Older Python - Similar to "uniq | sort"

# But it only works for Python 3.6 and above

# For Python 2.7 and 3.0-3.5, use OrderedDict:from collections import OrderedDict

list(OrderedDict.fromkeys(DUPLICATES))

#### METHOD 5 ###

# Crunch duplicates as they appear and show count

# Similar to bashes "uniq -c"

# I will show you how to do "uniq -c" on a string

# Just change the input to a list and it will work on a list

# METHOD 5.1 #

from itertools import groupby

input = "Raaanndommmm Leetters"

for i,v in groupby(input):

print(len(list(v)),i)

# Output:

1 R

3 a

2 n

1 d

1 o

4 m

1 L

2 e

2 t

1 e

1 r

1 s

# METHOD 5.2 #

# Or you can return a list for an output:

l=[]

for i,v in groupby(input):

l.append(str(len(list(v)))+" "+str(i))

print(l)

# Output:

['1 R', '3 a', '2 n', '1 d', '1 o', '4 m', '1 ', '1 L', '2 e', '2 t', '1 e', '1 r', '1 s']

# METHOD 5.3 #

# Same solution as a one liner:

print([ str(len(list(v)))+" "+str(i) for i,v in groupby(input)])

# Output:

['1 R', '3 a', '2 n', '1 d', '1 o', '4 m', '1 ', '1 L', '2 e', '2 t', '1 e', '1 r', '1 s']

### METHOD 6 ###

# Crunch out duplicates but dont show count

# METHOD 6.1 #

from itertools import groupby

input = "Raaanndommmm Leetters"

for i,v in groupby(input):

print(str(i))

# Output:

# METHOD 6.2 #

l=[]

for i,v in groupby(input):

l.append(str(i))

print(l)

# Output:

['R', 'a', 'n', 'd', 'o', 'm', ' ', 'L', 'e', 't', 'e', 'r', 's']

# METHOD 6.3 #

print([ str(i) for i,v in groupby(input)])

# Output:

['R', 'a', 'n', 'd', 'o', 'm', ' ', 'L', 'e', 't', 'e', 'r', 's']

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Monthly Archives: October 2020

Python + Guitar + All Notes

Python remove duplicates similar to bash uniq + sort