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Unique fields that allow nulls in Django
...trings are equal to empty strings for uniqueness checks, under both Django and database rules.
You can force the admin interface to store NULL for an empty string by providing your own customized model form for Foo with a clean_bar method that turns the empty string into None:
class FooForm(forms....
How to get last items of a list in Python?
I need the last 9 numbers of a list and I'm sure there is a way to do it with slicing, but I can't seem to get it. I can get the first 9 like this:
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How can I check whether a numpy array is empty or not?
...an always take a look at the .size attribute. It is defined as an integer, and is zero (0) when there are no elements in the array:
import numpy as np
a = np.array([])
if a.size == 0:
# Do something when `a` is empty
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Why does Java allow us to compile a class with a name different than the file name?
I have a file Test.java and the following code inside it.
8 Answers
8
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CSS way to horizontally align table
... a table using CSS. Conforming browsers ought to center tables if the left and right margins are equal. The simplest way to accomplish this is to set the left and right margins to “auto.” Thus, one might write in a style sheet:
table
{
margin-left: auto;
margin-right: auto;
}
But th...
How to change line width in IntelliJ (from 120 character)
...hould activate Settings -> Editor -> Java/Groovy/JSON -> Wrapping and Braces -> Ensure right margin is not exceeded
– Edu Castrillon
Oct 15 '15 at 15:26
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Entity Framework. Delete all rows in table
...
For those that are googling this and ended up here like me, this is how you currently do it in EF5 and EF6:
context.Database.ExecuteSqlCommand("TRUNCATE TABLE [TableName]");
Assuming context is a System.Data.Entity.DbContext
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Error installing mysql2: Failed to build gem native extension
...
On Ubuntu/Debian and other distributions using aptitude:
sudo apt-get install libmysql-ruby libmysqlclient-dev
Package libmysql-ruby has been phased out and replaced by ruby-mysql. This is where I found the solution.
If the above command ...
How to get the current directory in a C program?
...is program is written for UNIX computers. I've been looking at opendir() and telldir() , but telldir() returns a off_t (long int) , so it really doesn't help me.
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ContextLoaderListener or not?
A standard spring web application (created by Roo or "Spring MVC Project" Template) create a web.xml with ContextLoaderListener and DispatcherServlet . Why do they not only use the DispatcherServlet and make it to load the complete configuration?
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