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Group by multiple columns in dplyr, using string vector input
...cumentation here). This lets you use the same functions you would use with select, like so:
data = data.frame(
asihckhdoydkhxiydfgfTgdsx = sample(LETTERS[1:3], 100, replace=TRUE),
a30mvxigxkghc5cdsvxvyv0ja = sample(LETTERS[1:3], 100, replace=TRUE),
value = rnorm(100)
)
# get the column...
Postgres: “ERROR: cached plan must not change result type”
...ng this error.
My application opened a database connection and prepared a SELECT statement for execution.
Meanwhile, another script was modifying the database table, changing the data type of one of the columns being returned in the above SELECT statement.
I resolved this by restarting the applic...
How to calculate time in hours between two dates in iOS
...developer.apple.com/library/mac/navigation/
or if you are using Xcode just select help/documentation from the menu.
See: how-to-convert-an-nstimeinterval-seconds-into-minutes
--edit: See ÐąrέÐέvil's answer below for correctly handling daylight savings/leap seconds
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How do you test private methods with NUnit?
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This should be the selected answer, as it is the only one which actually answers the question.
– bavaza
Dec 10 '13 at 16:04
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Reset AutoIncrement in SQL Server after Delete
... a column(column_name) from a table(table1), you can use following query
SELECT MAX(column_name) FROM table1
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Can the :not() pseudo-class have multiple arguments?
I'm trying to select input elements of all type s except radio and checkbox .
5 Answers
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How can I connect to MySQL in Python 3 on Windows?
...k', user='root', passwd=None, db='mysql')
cur = conn.cursor()
cur.execute("SELECT Host,User FROM user")
for r in cur:
print(r)
cur.close()
conn.close()
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Context switches much slower in new linux kernels
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One of the roles of BIOS feature selection is to enable/disable devices. In some cases these selections are forced on the OS (e.g., on-motherboard USB, eSATA and NICs). In others the OS is expected to respect your wishes (e.g., EIST, C states, Hyperthreading...
Fastest way to extract frames using ffmpeg?
...actly which frames to extract, eg 1, 200, 400, 600, 800, 1000, try using:
select='eq(n\,1)+eq(n\,200)+eq(n\,400)+eq(n\,600)+eq(n\,800)+eq(n\,1000)' \
-vsync vfr -q:v 2
I'm using this with a pipe to Imagemagick's montage to get 10 frames preview from any videos. Obviously the frame numbers ...
“User interaction is not allowed” trying to sign an OSX app using codesign
...ish agrawal!
Login your build user via the GUI and open Keychain Access. Select your signing private key, right-click, choose Get Info, change to the Access Control tab and select the "Allow all applications to access this item".
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