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Referring to the null object in Python
...entity operator, which tests that two variables refer to the same object.
>>> foo is None
True
>>> foo = 'bar'
>>> foo is None
False
The basics
There is and can only be one None
None is the sole instance of the class NoneType and any further attempts at instantiating that...
How to add JTable in JPanel with null layout?
...awt.event.ActionEvent;
import javax.swing.*;
import javax.swing.table.DefaultTableModel;
import javax.swing.border.TitledBorder;
/** A short example of a nested layout that can change PLAF at runtime.
The TitledBorder of each JPanel shows the layouts explicitly set.
@author Andrew Thompson
@version...
What are differences between AssemblyVersion, AssemblyFileVersion and AssemblyInformationalVersion?
...ssemblyVersion is required.
I use the format: major.minor. This would result in:
[assembly: AssemblyVersion("1.0")]
If you're following SemVer strictly then this means you only update when the major changes, so 1.0, 2.0, 3.0, etc.
AssemblyFileVersion
Used for deployment. You can increase this ...
Removing All Child Views from View
... int childCount = v.getChildCount();
int i;
for(i=0; i<childCount; i++) {
View currentChild = v.getChildAt(i);
// Change ImageView with your desired type view
if (currentChild instanceof ImageView) {
v.removeView(currentChild...
What does numpy.random.seed(0) do?
...
np.random.seed(0) makes the random numbers predictable
>>> numpy.random.seed(0) ; numpy.random.rand(4)
array([ 0.55, 0.72, 0.6 , 0.54])
>>> numpy.random.seed(0) ; numpy.random.rand(4)
array([ 0.55, 0.72, 0.6 , 0.54])
With the seed reset (every time), the ...
Accessing items in an collections.OrderedDict by index
...ements by indexing by getting the tuples of (key,value) pairs as follows
>>> import collections
>>> d = collections.OrderedDict()
>>> d['foo'] = 'python'
>>> d['bar'] = 'spam'
>>> d.items()
[('foo', 'python'), ('bar', 'spam')]
>>> d.items()[0]
(...
Further understanding setRetainInstance(true)
...t()
TestActivity@415a4a30: onResume()
TestFragment{41583008}: onResume()
<rotate device>
TestFragment{41583008}: onPause()
TestActivity@415a4a30: onPause()
TestFragment{41583008}: onStop()
TestActivity@415a4a30: onStop()
TestFragment{41583008}: onDestroyView()
TestFragment{41583008}: onDetac...
Is it possible to use argsort in descending order?
...t reversed).
Example timings:
Using a small array of 100 floats and a length 30 tail, the view method was about 15% faster
>>> avgDists = np.random.rand(100)
>>> n = 30
>>> timeit (-avgDists).argsort()[:n]
1.93 µs ± 6.68 ns per loop (mean ± std. dev. of 7 runs, 10000...
How do I do a case-insensitive string comparison?
... which text.lower() != text.upper().lower(), such as "ß":
"ß".lower()
#>>> 'ß'
"ß".upper().lower()
#>>> 'ss'
But let's say you wanted to caselessly compare "BUSSE" and "Buße". Heck, you probably also want to compare "BUSSE" and "BUẞE" equal - that's the newer capital for...
Python nested functions variable scoping [duplicate]
... that is by using lists. For instance, if i want to do this:
X=0
While X<20:
Do something. ..
X+=1
I would instead do this:
X=[0]
While X<20:
Do something....
X[0]+=1
This way X is never a local variable
...