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How to implement an ordered, default dict? [duplicate]
I would like to combine OrderedDict() and defaultdict() from collections in one object, which shall be an ordered, default dict .
Is this possible?
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Breadth First Vs Depth First
... / / \
D E F
A depth first traversal would visit the nodes in this order
A, B, D, C, E, F
Notice that you go all the way down one leg before moving on.
A breadth first traversal would visit the node in this order
A, B, C, D, E, F
Here we work all the way across each level before going...
Remove all the elements that occur in one list from another
...- set([2,3,5,8])
set([1, 6])
Note, however, that sets do not preserve the order of elements, and cause any duplicated elements to be removed. The elements also need to be hashable. If these restrictions are tolerable, this may often be the simplest and highest performance option.
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How to remove jar file from local maven repository which was added with install:install-file?
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This approach also requires a maven project in order to run the command. This doesn't appear to work if you ran the install command that the OP specified in the context of say a Gradle build.
– jdonmoyer
Oct 24 '14 at 13:41
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PostgreSQL delete all content
...har(30),
constraint pk_customer primary key (customer_id)
);
create table orders (
order_id int not null,
number int not null,
customer_id int not null,
constraint pk_order primary key (order_id),
constraint fk_customer foreign key (customer_id) references customers(customer_id)
);
create table lo...
How to write to a file, using the logging Python module?
...Running Urban Planning")
self.logger = logging.getLogger('urbanGUI')
In order, the five parts do the following:
set the output file (filename=logname)
set it to append rather than overwrite (filemode='a')
determine the format of the output message (format=...)
determine the format of the outpu...
Virtual functions and performance - C++
...stion made me curious, so I went ahead and ran some timings on the 3GHz in-order PowerPC CPU we work with. The test I ran was to make a simple 4d vector class with get/set functions
class TestVec
{
float x,y,z,w;
public:
float GetX() { return x; }
float SetX(float to) { return x=to; }...
Why do people write the #!/usr/bin/env python shebang on the first line of a Python script?
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In order to run the python script, we need to tell the shell three things:
That the file is a script
Which interpreter we want to execute the script
The path of said interpreter
The shebang #! accomplishes (1.). The shebang ...
Insert ellipsis (…) into HTML tag if content too wide
... white-space: normal;
}
<div class="ellipsis" style="width: 100px; border: 1px solid black;">Lorem ipsum dolor sit amet, consectetur adipisicing elit</div>
<div class="ellipsis multiline" style="width: 100px; height: 40px; border: 1px solid black; margin-bottom: 100px">Lorem ip...
What's wrong with foreign keys?
...ost if you have a lot of churn
by enforcing relationships, FKs specify an order in which you have to add/delete things, which can lead to refusal by the DB to do what you want. (Granted, in such cases, what you are trying to do is create an Orphaned Row, and that's not usually a good thing). This...