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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
...
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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Types in Objective-C on iOS
...
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):
...
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 ...
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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ValueError: invalid literal for int() with base 10: ''
...ame)
for line in h:
if line.strip():
[int(next(h).strip()) for _ in range(4)] # list of integers
This way it processes 5 lines at the time. Use h.next() instead of next(h) prior to Python 2.6.
The reason you had ValueError is because int cannot convert an empty string to the integ...
In a storyboard, how do I make a custom cell for use with multiple controllers?
...lls out of a storyboard, here's what happens:
Each prototype cell is actually its own embedded mini-nib. So when the table view controller is loading up, it runs through each of the prototype cell's nibs and calls -[UITableView registerNib:forCellReuseIdentifier:].
The table view asks the controll...
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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Asynchronously load images with jQuery
...er.com/base64-encoder.html for image encoding.
$.ajax({
url : 'BASE64_IMAGE_REST_URL',
processData : false,
}).always(function(b64data){
$("#IMAGE_ID").attr("src", "data:image/png;base64,"+b64data);
});
Solution2:
Trick the browser to use its cache. This gives you a nice fadeIn() ...