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Python integer incrementing with ++ [duplicate]
...I've looked back at my VB6 days and thought, "What modern language doesn't allow incrementing with double plus signs?":
7 A...
Print string to text file
...t_file.close()
If you use a context manager, the file is closed automatically for you
with open("Output.txt", "w") as text_file:
text_file.write("Purchase Amount: %s" % TotalAmount)
If you're using Python2.6 or higher, it's preferred to use str.format()
with open("Output.txt", "w") as text...
C# Lazy Loaded Automatic Properties
... 4.0 Lazy<T> type to create this pattern
private Lazy<string> _someVariable =new Lazy<string>(SomeClass.IOnlyWantToCallYouOnce);
public string SomeVariable => _someVariable.Value;
This code will lazily calculate the value of _someVariable the first time the Value expression i...
LEFT JOIN only first row
... Thanks for your fast response. This was not the exact answer, but totally got me on the right way. I always tried to join both on the same level instead of making the one depended from the other. Thank you very much for leading me on the right track. Edited the first post
...
How to create a density plot in matplotlib?
...with R. This is because gaussian_kde tries to infer the bandwidth automatically. You can play with the bandwidth in a way by changing the function covariance_factor of the gaussian_kde class. First, here is what you get without changing that function:
However, if I use the following code:
import...
What is the fastest way to check if a class has a function defined?
...tr() to get the attribute, and callable() to verify it is a method:
invert_op = getattr(self, "invert_op", None)
if callable(invert_op):
invert_op(self.path.parent_op)
Note that getattr() normally throws exception when the attribute doesn't exist. However, if you specify a default value (None...
How can I make the cursor turn to the wait cursor?
... it takes a little while to do. How can I display the Wait/Busy Cursor (usually the hourglass) to the user to let them know the program is doing something?
...
How to check null objects in jQuery
...em to have enough reputation to vote down the answer...)
Wolf wrote:
Calling length property on undefined
or a null object will cause IE and
webkit browsers to fail!
Instead try this:
// NOTE!! THE FOLLOWING IS WRONG; DO NOT USE! -- EleotleCram
if($("#something") !== null){
// do ...
sqlalchemy unique across multiple columns
... declares those in the table definition, or if using declarative as in the __table_args__:
# version1: table definition
mytable = Table('mytable', meta,
# ...
Column('customer_id', Integer, ForeignKey('customers.customer_id')),
Column('location_code', Unicode(10)),
UniqueConstraint...
Passing parameters in rails redirect_to
How do we pass parameters in redirect_to in rails?
I know we can pass id using this:
9 Answers
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