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django admin - add custom form fields that are not part of the model
... ModelForm class and then declare your extra fields inside that as you normally would. I've also given an example of how you might use these values in form.save():
from django import forms
from yourapp.models import YourModel
class YourModelForm(forms.ModelForm):
extra_field = forms.CharFiel...
How to make rounded percentages add up to 100%
...55310199789695, 8.780231335436383, 8.04416403785489, 0]. The last one logically returns -1. I thought of the following solution really quickly but there's probably something better: jsfiddle.net/0o75bw43/1
– Cruclax
Aug 5 '16 at 16:39
...
Export specific rows from a PostgreSQL table as INSERT SQL script
....5.3, and my create statement was the same as yours except create view.... All I get in the output is the usual pg_dump comments and SET statements. Not sure where I'm going wrong.
– poshest
Nov 20 '16 at 15:19
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Quickly find whether a value is present in a C array?
...ned assembly language. I tend to take the path of least resistance - for small routines like this, I just write asm code and have a good idea how many cycles it will take to execute. You may be able to fiddle with the C code and get the compiler to generate good output, but you may end up wasting lo...
Suppressing deprecated warnings in Xcode
With all the SDKs floating around, it's handy to be able to build for multiple SDKs and platforms. However, bouncing from 3.2 to 3.0 and even occasionally 2.x, I frequently get deprecated warnings involving methods that have changed or been superseded:
...
Why does modern Perl avoid UTF-8 by default?
...?????????????????????
Set your PERL_UNICODE envariable to AS. This makes all Perl scripts decode @ARGV as UTF‑8 strings, and sets the encoding of all three of stdin, stdout, and stderr to UTF‑8. Both these are global effects, not lexical ones.
At the top of your source file (program, module, l...
What is a proper naming convention for MySQL FKs?
...constraints. If a name is not given, InnoDB creates a unique name automatically.
In any case, this is the convention that I use:
fk_[referencing table name]_[referenced table name]_[referencing field name]
Example:
CREATE TABLE users(
user_id int,
name varchar(100)
);
CREATE T...
SQL to determine minimum sequential days of access?
...
@Artem: That was what I initially thought but when I thought about it, if you have an index on (UserId, CreationDate), the records will show up consecutively in the index and it should perform well.
– Mehrdad Afshari
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How can I mock requests and the response?
...thons mock package to mock Pythons requests module. What are the basic calls to get me working in below scenario?
9 Answ...
Removing duplicates from a list of lists
... much easier that it offers good returns on efforts. But sometimes (essentially for "tragically crucial bottlenecks" in deep inner loops of code that's pushing the boundaries of performance limits) one may need to go into much more detail, providing probability distributions, deciding which performa...