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For loop example in MySQL
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drop table if exists foo;
create table foo
(
id int unsigned not null auto_increment primary k...
Converting a column within pandas dataframe from int to string
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In [16]: df = DataFrame(np.arange(10).reshape(5,2),columns=list('AB'))
In [17]: df
Out[17]:
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Execution failed app:processDebugResources Android Studio
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How can I add or update a query string parameter?
...])" + key + "=.*?(&|$)", "i");
var separator = uri.indexOf('?') !== -1 ? "&" : "?";
if (uri.match(re)) {
return uri.replace(re, '$1' + key + "=" + value + '$2');
}
else {
return uri + separator + key + "=" + value;
}
}
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Imply bit with constant 1 or 0 in SQL Server
Is it possible to express 1 or 0 as a bit when used as a field value in a select statement?
8 Answers
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How to remove from a map while iterating it?
... (must_delete)
{
m.erase(it++); // or "it = m.erase(it)" since C++11
}
else
{
++it;
}
}
Note that we really want an ordinary for loop here, since we are modifying the container itself. The range-based loop should be strictly reserved for situations where we only care about the...
How to avoid warning when introducing NAs by coercion
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Use suppressWarnings():
suppressWarnings(as.numeric(c("1", "2", "X")))
[1] 1 2 NA
This su...
How to compare two dates?
...rt datetime, timedelta
>>> past = datetime.now() - timedelta(days=1)
>>> present = datetime.now()
>>> past < present
True
>>> datetime(3000, 1, 1) < present
False
>>> present - datetime(2000, 4, 4)
datetime.timedelta(4242, 75703, 762105)
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Why are elementwise additions much faster in separate loops than in a combined loop?
Suppose a1 , b1 , c1 , and d1 point to heap memory and my numerical code has the following core loop.
10 Answers
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Remove unwanted parts from strings in a column
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173
data['result'] = data['result'].map(lambda x: x.lstrip('+-').rstrip('aAbBcC'))
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