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How to select rows from a DataFrame based on column values?
...have multiple values you want to include, put them in a
list (or more generally, any iterable) and use isin:
print(df.loc[df['B'].isin(['one','three'])])
yields
A B C D
0 foo one 0 0
1 bar one 1 2
3 bar three 3 6
6 foo one 6 12
7 foo three 7 14
Note,...
Create code first, many to many, with additional fields in association table
...join table. In a many-to-many relationship EF manages the join table internally and hidden. It's a table without an Entity class in your model. To work with such a join table with additional properties you will have to create actually two one-to-many relationships. It could look like this:
public c...
Why can't yield return appear inside a try block with a catch?
...ty. I suspect there are very, very few times where this restriction is actually an issue that can't be worked around - but the added complexity in the compiler would be very significant.
There are a few things like this that I've already encountered:
Attributes not being able to be generic
Inabil...
Returning JSON from PHP to JavaScript?
I have a PHP script that's being called through jQuery AJAX. I want the PHP script to return the data in JSON format to the javascript. Here's the pseudo code in the PHP script:
...
Fastest sort of fixed length 6 int array
...ction pipeline to stall.
Here's an insertion sort implementation:
static __inline__ int sort6(int *d){
int i, j;
for (i = 1; i < 6; i++) {
int tmp = d[i];
for (j = i; j >= 1 && tmp < d[j-1]; j--)
d[j] = d[j-1]...
Implementing MVC with Windows Forms
...ation of MVC (or MVP) that always fits well.
The best posts I have seen really explaining MVC and why an MVC system is built the way it is, is the "Build Your Own CAB" series by Jeremy D Miller. After working though it you should be able to understand your options a lot better.
Microsoft's Smart Cl...
How to migrate back from initial migration in Django 1.7?
...lt;app> zero
This clears <app> from migration history and drops all tables of <app>
See django docs for more info.
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Should everything really be a bundle in Symfony 2.x?
...,
etc.
This way, you would put in the AppBundle only that stuff that is really Symfony2 specific. If you decide to switch to another framework later, you would get rid of the Bundle namespace and replace it with the chosen framework stuff.
Please note that what I'm suggesting here is for app specif...
MySQL Removing Some Foreign keys
...You can use this to find foreign key constraints: SELECT * FROM information_schema.table_constraints WHERE constraint_schema = '<your db name>' AND constraint_type = 'FOREIGN KEY'
– Gayan Dasanayake
Aug 26 '17 at 2:48
...
What are the most widely used C++ vector/matrix math/linear algebra libraries, and their cost and be
...t seems that many projects slowly come upon a need to do matrix math, and fall into the trap of first building some vector classes and slowly adding in functionality until they get caught building a half-assed custom linear algebra library, and depending on it.
...