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warning: [options] bootstrap class path not set in conjunction with -source 1.5
...va
On UNIX systems, locate rt.jar using:
locate -r '/rt.jar$'
Set JAVA_HOME so that rt.jar is located at $JAVA_HOME/jre/lib/rt.jar, then:
javac -source 1.7 -bootclasspath "$JAVA_HOME/jre/lib/rt.jar" Main.java
Tested on Ubuntu 14.04 for Oracle Java 7 and 8.
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postgresql COUNT(DISTINCT …) very slow
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You can use this:
SELECT COUNT(*) FROM (SELECT DISTINCT column_name FROM table_name) AS temp;
This is much faster than:
COUNT(DISTINCT column_name)
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SFTP in Python? (platform independent)
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@user443854 yes there is pysftp.readthedocs.io/en/release_0.2.9/… But I would definitely not recommend that, though you can add another known_host file
– AsTeR
Jul 17 '18 at 8:04
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Types in Objective-C on iOS
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This is a good overview:
http://reference.jumpingmonkey.org/programming_languages/objective-c/types.html
or run this code:
32 bit process:
NSLog(@"Primitive sizes:");
NSLog(@"The size of a char is: %d.", sizeof(char));
NSLog(@"The size of short is: %d.", sizeof(short));
NSLog(@"The si...
Applying function with multiple arguments to create a new pandas column
...f = pd.DataFrame({"A": [10,20,30], "B": [20, 30, 10]})
>>> df['new_column'] = np.multiply(df['A'], df['B'])
>>> df
A B new_column
0 10 20 200
1 20 30 600
2 30 10 300
or vectorize arbitrary function in general case:
>>> def fx(x, y):
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How do I update the notification text for a foreground service in Android?
... only by calling stopForground );
Example:
private static final int NOTIF_ID=1;
@Override
public void onCreate (){
this.startForeground();
}
private void startForeground() {
startForeground(NOTIF_ID, getMyActivityNotification(""));
}
private Notification getMyActivityNotification(String...
JavaScript regex multiline flag doesn't work
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Can I use: caniuse.com/#feat=mdn-javascript_builtins_regexp_dotall MDN: developer.mozilla.org/ru/docs/Web/JavaScript/Reference/…
– Filyus
Aug 19 at 9:44
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How can I pass a Bitmap object from one activity to another
... on external storage and pass just the URI.
– AITAALI_ABDERRAHMANE
Sep 14 '15 at 20:28
1
what is ...
Rebasing remote branches in Git
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@r_: Please read my answer. It might help you in your understanding of what you're doing :)
– ralphtheninja
Jun 1 '11 at 19:28
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Python strptime() and timezones?
...time module documentation says:
Return a datetime corresponding to date_string, parsed according to format. This is equivalent to datetime(*(time.strptime(date_string, format)[0:6])).
See that [0:6]? That gets you (year, month, day, hour, minute, second). Nothing else. No mention of timezones....