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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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What's the correct way to sort Python `import x` and `from x import y` statements?
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from nova.auth import users
from nova.endpoint import cloud
OR
import a_standard
import b_standard
import a_third_party
import b_third_party
from a_soc import f
from a_soc import g
from b_soc import d
Reddit official repository also states that, In general PEP-8 import ordering should be use...
Dialog to pick image from gallery or from camera
...ake picture from camera:
Intent takePicture = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
startActivityForResult(takePicture, 0);//zero can be replaced with any action code (called requestCode)
To pick photo from gallery:
Intent pickPhoto = new Intent(Intent.ACTION_PICK,
android.prov...
How do I build a numpy array from a generator?
...ess you either:
can predict how many elements it will yield when run:
my_array = numpy.empty(predict_length())
for i, el in enumerate(gimme()): my_array[i] = el
are willing to store its elements in an intermediate list :
my_array = numpy.array(list(gimme()))
can make two identical generators, ...
Reading in a JSON File Using Swift
...app due to uncaught exception 'NSInvalidArgumentException', reason: '*** -[_NSPlaceholderData initWithContentsOfFile:options:error:]: nil file argument' *** First throw call stack: Any ideas on why this is? For the jsonData options: I put (path, options: NSDataReadingOptions.DataReadingMappedIfSaf...
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...
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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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 to exit pdb and allow program to continue?
...) clear 1
Deleted breakpoint 1
(Pdb) continue
Or, if you're using pdb.set_trace(), you can try this (although if you're using pdb in more fancy ways, this may break things...)
(Pdb) pdb.set_trace = lambda: None # This replaces the set_trace() function!
(Pdb) continue
# No more breaks!
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