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Is there a reason for C#'s reuse of the variable in a foreach?
...n using lambda expressions or anonymous methods in C#, we have to be wary of the access to modified closure pitfall. For example:
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Multiple variables in a 'with' statement?
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is it possible set fields equal to something in with statement as in with open('./file') as arg.x = file:?
– Charlie Parker
Feb 3 '17 at 5:46
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How do you grep a file and get the next 5 lines
.../{c=5} c-->0'
awk '/19:55/{c=5} c && c--'
When pattern found, set c=5
If c is true, print and decrease number of c
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How to Remove ReadOnly Attribute on File Using PowerShell?
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You can use Set-ItemProperty:
Set-ItemProperty file.txt -name IsReadOnly -value $false
or shorter:
sp file.txt IsReadOnly $false
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MySQL table is marked as crashed and last (automatic?) repair failed
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If your MySQL process is running, stop it. On Debian:
sudo service mysql stop
Go to your data folder. On Debian:
cd /var/lib/mysql/$DATABASE_NAME
Try running:
myisamchk -r $TABLE_NAME
If that doesn't work, you can try...
jQuery Validate - Enable validation for hidden fields
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Release: Validation Plugin 1.9.0:
"...Another change should make the setup of forms with hidden elements
easier, these are now ignored by default (option “ignore” has
“:hidden” now as default). In theory, this could break an existing
setup. In the unlikely case that it actually d...
Print a list in reverse order with range()?
..., step) you have to use third parameter of range which identifies step and set it to -1, other parameters shall be adjusted accordingly:
Provide stop parameter as -1(it's previous value of stop - 1, stop was equal to 0).
As start parameter use n-1.
So equivalent of range(n) in reverse order woul...
File is universal (three slices), but it does not contain a(n) ARMv7-s slice error for static librar
...hitecture, for example, ARMv7-s in your case, use menu Project -> Build Settings -> remove the architecture from "valid architectures".
You can use this as a temporary solution until the library has been updated. You have to remove the architecture from your main project, not from the library...
Find column whose name contains a specific string
... This syntax is list comprehension.
If you only want the resulting data set with the columns that match you can do this:
df2 = df.filter(regex='spike')
print(df2)
Output:
spike-2 spiked-in
0 1 7
1 2 8
2 3 9
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Pandas get topmost n records within each group
...ata)
EDIT: As mentioned by the questioner, use df.groupby('id').head(2).reset_index(drop=True) to remove the multindex and flatten the results.
>>> df.groupby('id').head(2).reset_index(drop=True)
id value
0 1 1
1 1 2
2 2 1
3 2 2
4 3 1
5 4 1
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