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Explaining Python's '__enter__' and '__exit__'
...plained above, use this object with the with statement (you may need to do from __future__ import with_statement at the top of the file if you're on Python 2.5).
with DatabaseConnection() as mydbconn:
# do stuff
PEP343 -- The 'with' statement' has a nice writeup as well.
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How to resolve git's “not something we can merge” error
...hown in How does "not something we can merge" arise?, this error can arise from a typo in the branch name because you are trying to pull a branch that doesn't exist.
If that is not the problem (as in my case), it is likely that you don't have a local copy of the branch that you want to merge. Git r...
Rails: Using build with a has_one association in rails
...w the top rated and accepted answer here is answering a different question from the one the OP asked.
– Ajedi32
Jun 27 '14 at 15:31
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What is the purpose of shuffling and sorting phase in the reducer in Map Reduce Programming?
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First of all shuffling is the process of transfering data from the mappers to the reducers, so I think it is obvious that it is necessary for the reducers, since otherwise, they wouldn't be able to have any input (or input from every mapper). Shuffling can start even before the map ...
Get a substring of a char* [duplicate]
...that string data without copying it. If you take a pointer to the section from the original string you need to know the length as it will have no null terminator (Without affecting the original string).
– Goz
Nov 12 '13 at 6:56
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Django-DB-Migrations: cannot ALTER TABLE because it has pending trigger events
I want to remove null=True from a TextField:
5 Answers
5
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How do I format a number in Java?
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From this thread, there are different ways to do this:
double r = 5.1234;
System.out.println(r); // r is 5.1234
int decimalPlaces = 2;
BigDecimal bd = new BigDecimal(r);
// setScale is immutable
bd = bd.setScale(decimalPla...
Node.js throws “btoa is not defined” error
...eed to convert to Base64 you could do so using Buffer:
console.log(Buffer.from('Hello World!').toString('base64'));
Reverse (assuming the content you're decoding is a utf8 string):
console.log(Buffer.from(b64Encoded, 'base64').toString());
Note: prior to Node v4, use new Buffer rather than B...
Convert column classes in data.table
... You might want to add what names_factors is here. I guess it's taken from stackoverflow.com/a/20808945/1666063 so it's names_factors = c('fac1', 'fac2') in this case - which is column names.But it could also be column numbers for example 1;ncol(dt) which would convert all columns
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How to create streams from string in Node.Js?
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From node 10.17, stream.Readable have a from method to easily create streams from any iterable (which includes array literals):
const { Readable } = require("stream")
const readable = Readable.from(["input string"])
readab...