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Unique BooleanField value in Django?
...if you've set the boolean to True, make sure all others are set to False.
from django.db import transaction
class Character(models.Model):
name = models.CharField(max_length=255)
is_the_chosen_one = models.BooleanField()
def save(self, *args, **kwargs):
if not self.is_the_chos...
What methods of ‘clearfix’ can I use?
...pose!
Thierry also offers: "A word of caution: if you start a new project from scratch, go for it, but don’t swap this technique with the one you have now, because even though you do not support oldIE, your existing rules prevent collapsing margins."
Micro Clearfix
The most recent and globall...
Converting RGB to grayscale/intensity
When converting from RGB to grayscale, it is said that specific weights to channels R, G, and B ought to be applied. These weights are: 0.2989, 0.5870, 0.1140.
...
cartesian product in pandas
... you can produce a cartesian product using merge (like you would in SQL).
from pandas import DataFrame, merge
df1 = DataFrame({'key':[1,1], 'col1':[1,2],'col2':[3,4]})
df2 = DataFrame({'key':[1,1], 'col3':[5,6]})
merge(df1, df2,on='key')[['col1', 'col2', 'col3']]
Output:
col1 col2 col3
0 ...
How to log out user from web site using BASIC authentication?
Is it possible to log out user from a web site if he is using basic authentication?
22 Answers
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Lambda expression vs method reference [closed]
...t whether method refs clarify or obfuscate intent is whether it is obvious from context what is the shape of the function being represented. In some cases (e.g., map(Person::getLastName), its quite clear from the context that a function that maps one thing to another is required, and in cases like ...
How can I lock a file using java (if possible)
... opens a file using a FileReader. How can I prevent another (Java) process from opening this file, or at least notify that second process that the file is already opened? Does this automatically make the second process get an exception if the file is open (which solves my problem) or do I have to ex...
Remove a character from the end of a variable
...etion appends a / at the end of a directory name. How I can strip this off from a positional parameter?
4 Answers
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java.net.ConnectException: localhost/127.0.0.1:8080 - Connection refused
I am using xampp apache server to serve resources to the application from my machine. But i am getting the above error.
10...
How do I delete all untracked files from my working directory in Mercurial?
Is it possible to delete all untracked files from my working directory? Let's say I added a bunch of files to my working directory, didn't add them via 'hg add' and now want to get rid of those new files entirely?
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