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Converting a column within pandas dataframe from int to string
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142
In [16]: df = DataFrame(np.arange(10).reshape(5,2),columns=list('AB'))
In [17]: df
Out[17]:
...
Change column type from string to float in Pandas
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1337
+200
You h...
How to COUNT rows within EntityFramework without loading contents?
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124
Query syntax:
var count = (from o in context.MyContainer
where o.ID == '1'
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How to avoid warning when introducing NAs by coercion
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142
Use suppressWarnings():
suppressWarnings(as.numeric(c("1", "2", "X")))
[1] 1 2 NA
This su...
Print a file, skipping the first X lines, in Bash [duplicate]
I have a very long file which I want to print, skipping the first 1,000,000 lines, for example.
13 Answers
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Get query string parameters url values with jQuery / Javascript (querystring)
...n use this new API to get values from the location!
// Assuming "?post=1234&action=edit"
var urlParams = new URLSearchParams(window.location.search);
console.log(urlParams.has('post')); // true
console.log(urlParams.get('action')); // "edit"
console.log(urlParams.getAll('action')); // ["ed...
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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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...
Remove unwanted parts from strings in a column
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173
data['result'] = data['result'].map(lambda x: x.lstrip('+-').rstrip('aAbBcC'))
...