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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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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...
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...
How do I see what character set a MySQL database / table / column is?
...ER_SET_APPLICABILITY` CCSA
WHERE CCSA.collation_name = T.table_collation
AND T.table_schema = "schemaname"
AND T.table_name = "tablename";
For Columns:
SELECT character_set_name FROM information_schema.`COLUMNS`
WHERE table_schema = "schemaname"
AND table_name = "tablename"
AND column_na...
Getting back old copy paste behaviour in tmux, with mouse
... do in tmux to copy-paste (using the mouse, the keyboard works differently and it is not what I am interested about):
13 An...
How to change the Eclipse default workspace?
...hat should I do if want to change the root directory of eclipse (for file handing in java)?
– Dhruv Singhal
Aug 3 '18 at 13:59
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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...
Postgres: SQL to list table foreign keys
...to list all foreign keys for a given table? I know the table name / schema and I can plug that in.
23 Answers
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HTML Input=“file” Accept Attribute File Type (CSV)
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Well this is embarrassing... I found the solution I was looking for and it couldn't be simpler. I used the following code to get the desired result. Hope this helps someone in the future. Thanks everyone for your help.
<input id="fileSelect" type="file" accept=".csv, application/vnd.open...
Difference between Hive internal tables and external tables?
Can anyone tell me the difference between Hive's external table and internal tables.
I know the difference comes when dropping the table. I don't understand what you mean by the data and metadata is deleted in internal and only metadata is deleted in external tables.
Can anyone explain me in terms o...