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How to group dataframe rows into list in pandas groupby?
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What is the best regular expression to check if a string is a valid URL?
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What is the syntax to insert one list into another list in python?
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Do you mean append?
>>> x = [1,2,3]
>>> y = [4,5,6]
>>> x.append(y)
>>> x
[1, 2, 3, [4, 5, 6]]
Or merge?
>>> x = [1,2,3]
>>> y = [4,5,6]
>>> x + y
[1, 2, 3, 4, 5, 6]
>>> x.extend(y)
>&g...
Index all *except* one item in python
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115
For a list, you could use a list comp. For example, to make b a copy of a without the 3rd ele...
How can I plot with 2 different y-axes?
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127
update: Copied material that was on the R wiki at http://rwiki.sciviews.org/doku.php?id=tips:g...
Can dplyr package be used for conditional mutating?
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Use ifelse
df %>%
mutate(g = ifelse(a == 2 | a == 5 | a == 7 | (a == 1 & b == 4), 2,
ifelse(a == 0 | a == 1 | a == 4 | a == 3 | c == 4, 3, NA)))
Added - if_else: Note that in dplyr 0.5 there is an if_else function defined so an alternative would be to replace ifelse with i...
Logical operators for boolean indexing in Pandas
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219
When you say
(a['x']==1) and (a['y']==10)
You are implicitly asking Python to convert (a['x'...
Convert column classes in data.table
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105
For a single column:
dtnew <- dt[, Quarter:=as.character(Quarter)]
str(dtnew)
Classes ‘...
Most popular screen sizes/resolutions on Android phones [closed]
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61
You can see the resolutions for those categories in the Table 2, in this section: http://develop...