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How can I obtain the element-wise logical NOT of a pandas Series?
... the bitwise operator:
In [1]: ~True
Out[1]: -2
As @geher says, you can convert it to bool with astype before you inverse with ~
~df['A'].astype(bool)
0 False
1 True
Name: A, dtype: bool
(~df['A']).astype(bool)
0 True
1 True
Name: A, dtype: bool
...
How to merge a list of lists with same type of items to a single list of items?
... @SwimBikeRun SelectMany is used to take an IEnumerable of TSources, convert each TSource in the list into an IEnumerable of TResults, then concatenate all those IEnumerables into one big one. In this case you have a list of lists to start, so if you want to concatenate them the function to ma...
Best practices/performance: mixing StringBuilder.append with String.concat
...done automatically by the compiler.
The Java2 compiler will automatically convert the following:
String s = s1 + s2;
to
String s = (new StringBuffer()).append(s1).append(s2).toString();
Taken straight from the Java Best Practices on Oracles website.
...
How to calculate the difference between two dates using PHP?
... up to date solution see jurka's answer below
You can use strtotime() to convert two dates to unix time and then calculate the number of seconds between them. From this it's rather easy to calculate different time periods.
$date1 = "2007-03-24";
$date2 = "2009-06-26";
$diff = abs(strtotime($date...
How to set DialogFragment's width and height?
...
If you convert directly from resources values:
int width = getResources().getDimensionPixelSize(R.dimen.popup_width);
int height = getResources().getDimensionPixelSize(R.dimen.popup_height);
getDialog().getWindow().setLayou...
ASP.NET MVC: Custom Validation by DataAnnotation
...<string>();
var totalLength = values.Sum(x => x.Length) + Convert.ToString(value).Length;
if (totalLength < this.MinLength)
{
return new ValidationResult(this.FormatErrorMessage(validationContext.DisplayName));
}
return null;
}
}
...
How do I use arrays in C++?
...ly "connection" between T[n] and T[m] is that both types can implicitly be converted to T*, and the result of this conversion is a pointer to the first element of the array. That is, anywhere a T* is required, you can provide a T[n], and the compiler will silently provide that pointer:
...
Date vs DateTime
...eTimeKind.Unspecified so that when serialized it gets deserialized without converting (may change date based upon different in timezones).
– oatsoda
Jul 30 '14 at 9:20
1
...
switch / pattern matching idea
...s. [Side note - if you look at the output of the C# compiler it frequently converts switch statements to dictionary-based jump tables, so there doesn't appear to be a good reason it couldn't support switching on types]
share...
SQLAlchemy: print the actual query
...
very nice. but is it converting as below. 1) query(Table).filter(Table.Column1.is_(False) to WHERE Column1 IS 0. 2) query(Table).filter(Table.Column1.is_(True) to WHERE Column1 IS 1. 3) query(Table).filter(Table.Column1 == func.any([1,2,3])) to W...