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Some questions about Automatic Reference Counting in iOS5 SDK
... existing code, you can keep using it as is with the -fno-objc-arc you can selectively disable ARC on any file.
If you want to disable ARC on MULTIPLE files:
Select desired files at Target/Build Phases/Compile Sources in Xcode
PRESS ENTER. (double click selects only one file)
Type -fno-objc-arc...
How to select the rows with maximum values in each group with dplyr? [duplicate]
I would like to select a row with maximum value in each group with dplyr.
6 Answers
6
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Split a collection into `n` parts with LINQ?
... group item by i++ % parts into part
select part.AsEnumerable();
return splits;
}
}
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Converting a Java Keystore into PEM Format
...
KeyStore ks = KeyStore.getInstance("jks");
/* Load the key store. */
...
char[] password = ...;
/* Save the private key. */
FileOutputStream kos = new FileOutputStream("tmpkey.der");
Key pvt = ks.getKey("your_alias", password);
kos.write(pvt.getEncoded());
kos.flush();
kos.close();
/* Save the cer...
Select Pandas rows based on list index
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For large datasets, it is memory efficient to read only selected rows via the skiprows parameter.
Example
pred = lambda x: x not in [1, 3]
pd.read_csv("data.csv", skiprows=pred, index_col=0, names=...)
This will now return a DataFrame from a file that skips all rows except 1 and ...
SQL Server Management Studio, how to get execution time down to milliseconds
...able in your proc:
DECLARE @EndTime datetime
DECLARE @StartTime datetime
SELECT @StartTime=GETDATE()
-- Write Your Query
SELECT @EndTime=GETDATE()
--This will return execution time of your query
SELECT DATEDIFF(ms,@StartTime,@EndTime) AS [Duration in millisecs]
AND see this
Measuring Quer...
Python/postgres/psycopg2: getting ID of row just inserted
... case you can use:
cursor.execute('INSERT INTO ........')
cursor.execute('SELECT LASTVAL()')
lastid = cursor.fetchone()['lastval']
Just in case it was useful for anyone!
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SQL Server: Get data for only the past year
...
The following adds -1 years to the current date:
SELECT ... From ... WHERE date > DATEADD(year,-1,GETDATE())
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String is immutable. What exactly is the meaning? [duplicate]
...
A string is a char[] containing a series of UTF-16 code units, an int offset into that array, and an int length.
For example.
String s
It creates space for a string reference. Assigning copies references around but does not modify the...
How to link to specific line number on github
...s://github.com/git/git/blob/master/README#L18
If you want multiple lines selected, simply hold down the shift key and click a second line number, like line 20. Looks like this:
And now your browser's URL looks like this:
https://github.com/git/git/blob/master/README#L18-L20
Here's the import...