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How to delete or add column in SQLITE?
...upports a limited subset of ALTER TABLE. The ALTER TABLE command in SQLite allows the user to rename a table or to add a new column to an existing table. It is not possible to rename a column, remove a column, or add or remove constraints from a table.
You can:
create new table as the one you ar...
How to list all tags along with the full message in git?
I want git to list all tags along with the full annotation or commit message. Something like this is close:
8 Answers
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Cosine Similarity between 2 Number Lists
... scientific routines for example, "routines for computing integrals numerically, solving differential equations, optimization, and sparse matrices." It uses the superfast optimized NumPy for its number crunching. See here for installing.
Note that spatial.distance.cosine computes the distance, and ...
Installing Python 3 on RHEL
I'm trying to install python3 on RHEL using the following steps:
19 Answers
19
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What is the reason why “synchronized” is not allowed in Java 8 interface methods?
...t seem sensible to extend this semantics to default methods as well; after all, they are instance methods with a receiver too. (Note that synchronized methods are entirely a syntactic optimization; they're not needed, they're just more compact than the corresponding synchronized block. There's a r...
Circular list iterator in Python
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Output:
a b c a b c ...
(Loops forever, obviously)
In order to manually advance the iterator and pull values from it one by one, simply call next(pool):
>>> next(pool)
'a'
>>> next(pool)
'b'
share...
When to use in vs ref vs out
...ss you need ref.
It makes a big difference when the data needs to be marshalled e.g. to another process, which can be costly. So you want to avoid marshalling the initial value when the method doesn't make use of it.
Beyond that, it also shows the reader of the declaration or the call whether the ...
How do I get a list of column names from a psycopg2 cursor?
... to generate column labels directly from the selected column names, and recall seeing that python's psycopg2 module supports this feature.
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Specifying rails version to use when creating a new application
I have two versions of rails (2.1.0 and 2.2.2) installed in my computer.
7 Answers
7
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Looking to understand the iOS UIViewController lifecycle
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All these commands are called automatically at the appropriate times by iOS when you load/present/hide the view controller. It's important to note that these methods are attached to UIViewController and not to UIViews themsel...