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Rails: Adding an index after adding column
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answered Apr 8 '13 at 14:31
Jaap HaagmansJaap Haagmans
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Get column index from column name in python pandas
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Sure, you can use .get_loc():
In [45]: df = DataFrame({"pear": [1,2,3], "apple": [2,3,4], "orange": [3,4,5]})
In [46]: df.columns
Out[46]: Index([apple, orange, pear], dtype=object)
In [47]: df.columns.get_loc("pear")
Out[47]: 2
although to be honest I do...
How do I move a single folder from one Subversion repository to another repository?
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edited Jul 4 '09 at 13:36
Mehrdad Afshari
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Why is LINQ JOIN so much faster than linking with WHERE?
...Where condition is evaluated for each combination of rows (n1 * n2 * n3 * n4)
The Join operator takes the rows from the first tables, then takes only the rows with a matching key from the second table, then only the rows with a matching key from the third table, and so on. This is much more efficien...
If table exists drop table then create it, if it does not exist just create it
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4 Answers
4
Active
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Stack vs heap allocation of structs in Go, and how they relate to garbage collection
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return chunk, nil
}
type bigStruct struct {
lots [1e6]float64
}
func myFunction3() (bigStruct, error) {
var chunk bigStruct
// ...
return chunk, nil
}
I modified myFunction2 to return the struct rather than the address of the struct. Compare the assembly output of myFu...
What is the difference between location list and quickfix list in vim
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edited Dec 11 '14 at 14:28
answered Jan 5 '14 at 14:18
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How long does it take for GitHub page to show changes after changing index.html
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answered Jul 21 '14 at 18:12
Joel GlovierJoel Glovier
6,60188 gold badges4444 silver badges8383 bronze badges
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Bash conditionals: how to “and” expressions? (if [ ! -z $VAR && -e $VAR ])
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534
if [ ! -z "$var" ] && [ -e "$var" ]; then
# something ...
fi
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On delete cascade with doctrine2
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417
There are two kinds of cascades in Doctrine:
1) ORM level - uses cascade={"remove"} in the as...