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Chrome: timeouts/interval suspended in background tabs?
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91
I recently asked about this and it is behaviour by design. When a tab is inactive, only at a max...
Alter Table Add Column Syntax
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198
Just remove COLUMN from ADD COLUMN
ALTER TABLE Employees
ADD EmployeeID numeric NOT NULL ID...
Is it possible to view RabbitMQ message contents directly from the command line?
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107
You should enable the management plugin.
rabbitmq-plugins enable rabbitmq_management
See he...
MongoDB Aggregation: How to get total records count?
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13 Answers
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Active
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Pandas count(distinct) equivalent
...()
Example:
In [2]: table
Out[2]:
CLIENTCODE YEARMONTH
0 1 201301
1 1 201301
2 2 201301
3 1 201302
4 2 201302
5 2 201302
6 3 201302
In [3]: table.groupby('YEARMONTH').CLIENTCODE.nunique()
Out[3...
binning data in python with scipy/numpy
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184
It's probably faster and easier to use numpy.digitize():
import numpy
data = numpy.random.ran...
Generate random password string with requirements in javascript
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18 Answers
18
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Why does X[Y] join of data.tables not allow a full outer join, or a left join?
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To quote from the data.table FAQ 1.11 What is the difference between X[Y] and merge(X, Y)?
X[Y] is a join, looking up X's rows using Y (or Y's key if it has one) as an index.
Y[X] is a join, looking up Y's rows using X (or X's key if it has one)
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How to delete an element from an array in C#
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10 Answers
10
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Signed to unsigned conversion in C - is it always safe?
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Your i will be converted to an unsigned integer by adding UINT_MAX + 1, then the addition will be carried out with the unsigned values, resulting in a large result (depending on the values of u and i).
Long Answer
According to the C99 Standard:
6.3.1.8 Usual arithmetic conversions
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