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Is it possible for a computer to “learn” a regular expression by user-provided examples?
...ton, it is possible to learn some regular expressions by a program. Kearns and Valiant show some cases where it is not possible to learn a finite automaton. A related problem is learning hidden Markov Models, which are probabilistic automata that can describe a character sequence. Note that most mod...
How to print out more than 20 items (documents) in MongoDB's shell?
... @LukaszWiktor yes, you can create a $HOME/.mongorc.js file and put that shellBatchSize setting in there. mine has the query batch size setting and rs.slaveOk() enabled. it's usage is also slightly different when using --eval via commandline. see: docs.mongodb.com/manual/mongo/#mongor...
In a django model custom save() method, how should you identify a new object?
...exes on other fields). In that case, you could still have a new record in hand, but be unable to save it.
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Physical vs. logical / soft delete of database record?
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Advantages are that you keep the history (good for auditing) and you don't have to worry about cascading a delete through various other tables in the database that reference the row you are deleting. Disadvantage is that you have to code any reporting/display methods to take the flag ...
How to remove all the occurrences of a char in c++ string
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Basically, replace replaces a character with another and '' is not a character. What you're looking for is erase.
See this question which answers the same problem. In your case:
#include <algorithm>
str.erase(std::remove(str.begin(), str.end(), 'a'), str.end());
Or us...
Returning the product of a list
...sing lambda:
from operator import mul
reduce(mul, list, 1)
it is better and faster. With python 2.7.5
from operator import mul
import numpy as np
import numexpr as ne
# from functools import reduce # python3 compatibility
a = range(1, 101)
%timeit reduce(lambda x, y: x * y, a) # (1)
%timeit r...
Connection timeout for SQL server
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Yes, you could append ;Connection Timeout=30 to your connection string and specify the value you wish.
The timeout value set in the Connection Timeout property is a time expressed in seconds. If this property isn't set, the timeout value for the connection is the default value (15 seconds).
Mo...
How do I partially update an object in MongoDB so the new object will overlay / merge with the exist
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If I understand the question correctly, you want to update a document with the contents of another document, but only the fields that are not already present, and completely ignore the fields that are already set (even if to another valu...
How do I trim whitespace from a string?
How do I remove leading and trailing whitespace from a string in Python?
12 Answers
12...
What are “signed” cookies in connect/expressjs?
...igure out what "signed cookies" actually are.
There isn't much on the net, and if I try this:
4 Answers
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