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Split delimited strings in a column and insert as new rows [duplicate]
...is another way of doing it..
df <- read.table(textConnection("1|a,b,c\n2|a,c\n3|b,d\n4|e,f"), header = F, sep = "|", stringsAsFactors = F)
df
## V1 V2
## 1 1 a,b,c
## 2 2 a,c
## 3 3 b,d
## 4 4 e,f
s <- strsplit(df$V2, split = ",")
data.frame(V1 = rep(df$V1, sapply(s, length))...
How to select rows from a DataFrame based on column values?
... three'.split(),
'C': np.arange(8), 'D': np.arange(8) * 2})
print(df)
# A B C D
# 0 foo one 0 0
# 1 bar one 1 2
# 2 foo two 2 4
# 3 bar three 3 6
# 4 foo two 4 8
# 5 bar two 5 10
# 6 foo one 6 12
# 7 foo three 7 14
pri...
how to change default python version?
I have installed python 3.2 in my mac. After I run /Applications/Python 3.2/Update Shell Profile.command , it's confusing that when I type python -V in Terminal it says that Python 2.6.1 , how can I change the default python version?
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How can I sort a dictionary by key?
What would be a nice way to go from {2:3, 1:89, 4:5, 3:0} to {1:89, 2:3, 3:0, 4:5} ?
I checked some posts but they all use the "sorted" operator that returns tuples.
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Remove all the elements that occur in one list from another
Let's say I have two lists, l1 and l2 . I want to perform l1 - l2 , which returns all elements of l1 not in l2 .
7 ...
Center a popup window on screen?
...temZoom = width / window.screen.availWidth;
const left = (width - w) / 2 / systemZoom + dualScreenLeft
const top = (height - h) / 2 / systemZoom + dualScreenTop
const newWindow = window.open(url, title,
`
scrollbars=yes,
width=${w / systemZoom},
height=${h / sys...
Algorithm to find Largest prime factor of a number
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27 Answers
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How to create a numpy array of all True or all False?
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295
numpy already allows the creation of arrays of all ones or all zeros very easily:
e.g. numpy....
cocktail party algorithm SVD implementation … in one line of code?
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2 Answers
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