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What's the difference between a single precision and double precision floating point operation?
What is the difference between a single precision floating point operation and double precision floating operation?
11 Answ...
How to create a numpy array of all True or all False?
...s very easily:
e.g. numpy.ones((2, 2)) or numpy.zeros((2, 2))
Since True and False are represented in Python as 1 and 0, respectively, we have only to specify this array should be boolean using the optional dtype parameter and we are done.
numpy.ones((2, 2), dtype=bool)
returns:
array([[ True, ...
How do I tell if a regular file does not exist in Bash?
...
The test command ([ here) has a "not" logical operator which is the exclamation point (similar to many other languages). Try this:
if [ ! -f /tmp/foo.txt ]; then
echo "File not found!"
fi
...
What are the most common SQL anti-patterns? [closed]
...d (or are learning) that SQL is different. Eliciting the desired results, and doing so efficiently, involves a tedious process partly characterized by learning unfamiliar paradigms, and finding out that some of our most familiar programming patterns don't work here. What are the common antipattern...
Which timestamp type should I choose in a PostgreSQL database?
...
First off, PostgreSQL’s time handling and arithmetic is fantastic and Option 3 is fine in the general case. It is, however, an incomplete view of time and timezones and can be supplemented:
Store the name of a user’s time zone as a user preference (e....
When should we implement Serializable interface?
...anisms are to
flatten object(s) into a
one-dimensional stream of bits, and to
turn that stream of bits back into the
original object(s).
Like the Transporter on Star Trek,
it's all about taking something
complicated and turning it into a flat
sequence of 1s and 0s, then taking
t...
Is C++ context-free or context-sensitive?
...uring-complete, since it shows a program which is syntactically correct if and only if a given integer is prime.
So I assert that C++ is neither context-free nor context-sensitive.
If you allow arbitrary symbol sequences on both sides of any production, you produce an Type-0 grammar ("unrestricted...
What's the difference between JPA and Spring Data JPA?
I am a bit confused about the difference between Spring Data-JPA and JPA. I know about JPA that it is a specification for persisting the Java Objects to a relational database using popular ORM technology.
...
Difference between Big-O and Little-O Notation
What is the difference between Big-O notation O(n) and Little-O notation o(n) ?
4 Answers
...
Shards and replicas in Elasticsearch
I am trying to understand what shard and replica is in Elasticsearch, but I didn't manage to understand it. If I download Elasticsearch and run the script, then from what I know I have started a cluster with a single node. Now this node (my PC) have 5 shards (?) and some replicas (?).
...