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Is gcc std::unordered_map implementation slow? If so - why?
...on: it is a Problem of gcc-4.7!!
With gcc-4.7
inserts: 37728
get : 2985
With gcc-4.6
inserts: 2531
get : 1565
So std::unordered_map in gcc-4.7 is broken (or my installation, which is an installation of gcc-4.7.0 on Ubuntu - and another installation which is gcc 4.7.1 on debian testing)....
Adding List.add() another list
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275
List<T>.Add adds a single element. Instead, use List<T>.AddRange to add multiple va...
MySQL: Invalid use of group function
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175
You need to use HAVING, not WHERE.
The difference is: the WHERE clause filters which rows MySQL...
Enabling error display in PHP via htaccess only
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5 Answers
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Right query to get the current number of connections in a PostgreSQL DB
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answered Mar 11 '11 at 8:52
Magnus HaganderMagnus Hagander
19.6k33 gold badges4848 silver badges4141 bronze badges
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For each row return the column name of the largest value
...ples using sample reproducible):
DF <- data.frame(V1=c(2,8,1),V2=c(7,3,5),V3=c(9,6,4))
colnames(DF)[apply(DF,1,which.max)]
[1] "V3" "V1" "V2"
A faster solution than using apply might be max.col:
colnames(DF)[max.col(DF,ties.method="first")]
#[1] "V3" "V1" "V2"
...where ties.method can be a...
Pythonic way to add datetime.date and datetime.time objects
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edited Dec 18 '17 at 3:52
Brad Solomon
25.2k1414 gold badges8989 silver badges148148 bronze badges
an...
Get all keys of an NSDictionary as an NSArray
...ys.firstObject;
– Islam Q.
Oct 20 '15 at 5:12
1
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Better way of getting time in milliseconds in javascript?
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5 Answers
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WPF TextBox won't fill in StackPanel
..."Orange" LastChildFill="True">
<TextBlock Text="a label" Margin="5"
DockPanel.Dock="Left" VerticalAlignment="Center"/>
<TextBox Height="25" Width="Auto"/>
</DockPanel >
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