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Multiple inheritance for an anonymous class
...ited Jun 5 '14 at 14:45
aspiring_sarge
1,84711 gold badge2222 silver badges3232 bronze badges
answered May 1 '11 at 13:04
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Understanding exactly when a data.table is a reference to (vs a copy of) another data.table
...00000000040ED948]:
# tracemem[00000000040ED948 -> 00000000040ED830]: .Call copy $<-.data.table $<-
.Internal(inspect(DT))
# @0000000003B7E2A0 19 VECSXP g0c7 [OBJ,NAM(2),TR,ATT] (len=2, tl=100)
# @00000000040C2288 14 REALSXP g0c2 [NAM(2)] (len=2, tl=0) 1,2
# @00000000040C2250 14 REALS...
Ruby on Rails: how to render a string as HTML?
...b>Hi</b>"
<%= @str.html_safe %>
Using raw works fine, but all it's doing is converting the string to a string, and then calling html_safe. When I know I have a string, I prefer calling html_safe directly, because it skips an unnecessary step and makes it clearer what's going on. Det...
Pass column name in data.table using variable [duplicate]
... I already have a gazillion column names in a character vector all there with double quotes around them. How do I get rid of the quotes?
– Farrel
Jun 28 '16 at 0:23
2
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Finding all possible permutations of a given string in python
I have a string. I want to generate all permutations from that string, by changing the order of characters in it. For example, say:
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Select by partial string from a pandas DataFrame
...egex search is not required, so specify regex=False to disable it.
#select all rows containing "foo"
df1[df1['col'].str.contains('foo', regex=False)]
# same as df1[df1['col'].str.contains('foo')] but faster.
col
0 foo
1 foobar
Performance wise, regex search is slower than substring s...
Difference between two lists
...'A','B','C'}.Except({'B','C'}) returns {'A'}
– digEmAll
Apr 12 '11 at 14:10
4
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Stack vs heap allocation of structs in Go, and how they relate to garbage collection
...le stack-based programming where automatic variables live on the stack and allocated memory lives on the heap and and Python-style stack-based-programming where the only thing that lives on the stack are references/pointers to objects on the heap.
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Go to back directory browsing after opening file in vim
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Nice thing summarizing all the other correct answers, I wish more people do that.
– LightMan
Jul 19 '18 at 8:57
1
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PreparedStatement IN clause alternatives?
... FROM my_table WHERE search_column = ? ; ... and execute it. [Or use UNION ALL in place of those semicolons. --ed] Requires one prepared statement per size-of-IN-list. Stupidly slow, strictly worse than WHERE search_column IN (?,?,?), so I don't know why the blogger even suggested it.
Use a stored p...