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data.table vs dplyr: can one do something well the other can't or does poorly?
... ## data.table syntax
left_join(DT2, DT1) ## dplyr syntax
# 2. select columns while join
DT1[DT2, .(z, i.mul)]
left_join(select(DT2, x, y, mul), select(DT1, x, y, z))
# 3. aggregate while join
DT1[DT2, .(sum(z) * i.mul), by = .EACHI]
DF1 %>% group_by(x, y) %>% summarise(z = su...
How do I get the n-th level parent of an element in jQuery?
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this will not work for multiple element selections, a safer way would be: $('.element').first().parents().eq(num);
– zzzzBov
Aug 17 '11 at 13:44
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Use didSelectRowAtIndexPath or prepareForSegue method for UITableView?
... I'll have to pass a couple objects to the detail view. But do I use didSelectRowAtIndex or -(void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender ?
...
How do I force detach Screen from another SSH session?
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Reattach without ejecting others: screen -x
Get list of displays: ^A *, select the one to disconnect, press d
Explained answer
Background: When I was looking for the solution with same problem description, I have always landed on this answer. I would like to provide more sensible solution. (...
Cannot find Dumpbin.exe
... Search for "command prompt" in the start menu, which brings up a selection of command prompts. Look for "Visual C++" or "Developer Studio" command prompts.
– edW
Feb 17 '19 at 23:26
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Eclipse add Tomcat 7 blank server name
...at 7 in my Eclipse in Ubuntu. When I click "Add new server" in Eclipse and select "Tomcat v7.0 Server", the field "Server Name" is blank and I cannot type in anything in that textbox as shown below:
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How do I enable standard copy paste for a TextView in Android?
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Try android:textIsSelectable.
i.e., android:textIsSelectable="true"
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Plurality in user messages
... are wrong. The correct way of doing this is:
string message = ( noofitemsselected==1 ?
"You have selected " + noofitemsselected + " item. Are you sure you want to delete it?":
"You have selected " + noofitemsselected + " items. Are you sure you want to delete them?"
);
This is because differ...
How to get a value from a cell of a dataframe?
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Most answers are using iloc which is good for selection by position.
If you need selection-by-label loc would be more convenient.
For getting a value explicitly (equiv to deprecated
df.get_value('a','A'))
# this is also equivalent to df1.at['a','A']
In [55]: df1....
How to comment out a block of code in Python [duplicate]
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vim with nerdcommenter. Select the block you want and ,c<space>
– dev_nut
Oct 10 '14 at 22:37
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