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Selecting a row of pandas series/dataframe by integer index
... edited Jun 5 '18 at 12:40
marc_aragones
3,37644 gold badges2323 silver badges3333 bronze badges
answered Apr 19 '13 at 12:20
...
How do I make a textbox that only accepts numbers?
... with this two event handlers on a standard TextBox:
private void textBox1_KeyPress(object sender, KeyPressEventArgs e)
{
if (!char.IsControl(e.KeyChar) && !char.IsDigit(e.KeyChar) &&
(e.KeyChar != '.'))
{
e.Handled = true;
}
// only allow one de...
How does lucene index documents?
...links . But i heard that Lucene project has a special stemmer named "Snowball"? Do you heard anything about that ?
– M.Amrollahi
Apr 9 '10 at 17:44
...
How can I index a MATLAB array returned by a function without first assigning it to a local variable
...
It actually is possible to do what you want, but you have to use the functional form of the indexing operator. When you perform an indexing operation using (), you are actually making a call to the subsref function. So, even though ...
How do you create different variable names while in a loop? [duplicate]
...can do this is with exec(). For example:
for k in range(5):
exec(f'cat_{k} = k*2')
>>> print(cat_0)
0
>>> print(cat_1)
2
>>> print(cat_2)
4
>>> print(cat_3)
6
>>> print(cat_4)
8
Here I am taking advantage of the handy f string formatting in Pytho...
Copy file or directories recursively in Python
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I suggest you first call shutil.copytree, and if an exception is thrown, then retry with shutil.copy.
import shutil, errno
def copyanything(src, dst):
try:
shutil.copytree(src, dst)
except OSError as exc: # python >2.5
...
Where does PostgreSQL store the database?
...here the data directory is, use this query.
show data_directory;
To see all the run-time parameters, use
show all;
You can create tablespaces to store database objects in other parts of the filesystem. To see tablespaces, which might not be in that data directory, use this query.
SELECT * FRO...
Cannot run Eclipse; JVM terminated. Exit code=13
...
Okey, I solve it. I just reinstall JDK 64-bit, re-extact eclipse-64bit and edit eclipse.ini again.
– Prince OfThief
Feb 9 '11 at 14:13
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C# pattern to prevent an event handler hooked twice [duplicate]
...ution and the best one (considering performance) is:
private EventHandler _foo;
public event EventHandler Foo {
add {
_foo -= value;
_foo += value;
}
remove {
_foo -= value;
}
}
No Linq using required. No need to check for null before cancelling a subscrip...
Co-variant array conversion from x to y may cause run-time exception
...js[0] = new Foo(); // again legal, with runtime exception
In C#, you are allowed to reference an array of objects (in your case, LinkLabels) as an array of a base type (in this case, as an array of Controls). It is also compile time legal to assign another object that is a Control to the array. Th...