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Paste multiple columns together
...
# your starting data..
data <- data.frame('a' = 1:3, 'b' = c('a','b','c'), 'c' = c('d', 'e', 'f'), 'd' = c('g', 'h', 'i'))
# columns to paste together
cols <- c( 'b' , 'c' , 'd' )
# create a new column `x` with the three columns collapsed together
data$x <- apply( d...
Build an ASCII chart of the most commonly used words in a given text [closed]
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123
votes
LabVIEW 51 nodes, 5 structures, 10 diagrams
Teaching the elephant to tap-dan...
How to write loop in a Makefile?
...by your use of ./a.out, you're on a UNIX-type platform.
for number in 1 2 3 4 ; do \
./a.out $$number ; \
done
Test as follows:
target:
for number in 1 2 3 4 ; do \
echo $$number ; \
done
produces:
1
2
3
4
For bigger ranges, use:
target:
number=1 ; while [[ $$number...
Why does SIGPIPE exist?
...|
edited Oct 26 '16 at 9:13
Ton van den Heuvel
8,39155 gold badges3434 silver badges7575 bronze badges
a...
Concatenating two one-dimensional NumPy arrays
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388
The line should be:
numpy.concatenate([a,b])
The arrays you want to concatenate need to passe...
Cosine Similarity between 2 Number Lists
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13 Answers
13
Active
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How to get item's position in a list?
...in enumerate(testlist) if x == 1]
Example:
>>> testlist
[1, 2, 3, 5, 3, 1, 2, 1, 6]
>>> [i for i,x in enumerate(testlist) if x == 1]
[0, 5, 7]
Update:
Okay, you want a generator expression, we'll have a generator expression. Here's the list comprehension again, in a for loop...
Getting key with maximum value in dictionary?
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632
You can use operator.itemgetter for that:
import operator
stats = {'a':1000, 'b':3000, 'c': 10...
Removing duplicates from a list of lists
...
>>> k = [[1, 2], [4], [5, 6, 2], [1, 2], [3], [4]]
>>> import itertools
>>> k.sort()
>>> list(k for k,_ in itertools.groupby(k))
[[1, 2], [3], [4], [5, 6, 2]]
itertools often offers the fastest and most powerful solutions to this kind of ...