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To find whether a column exists in data frame or not
...and that your column name to check is "d", you can use the %in% operator:
if("d" %in% colnames(dat))
{
cat("Yep, it's in there!\n");
}
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follo...
Can iterators be reset in Python?
... one crucial warning in the docs for it:
This itertool may require significant
auxiliary storage (depending on how
much temporary data needs to be
stored). In general, if one iterator
uses most or all of the data before
another iterator starts, it is faster
to use list() instead of t...
How to change a Git remote on Heroku
...
If you're working on the heroku remote (default):
heroku git:remote -a [app name]
If you want to specify a different remote, use the -r argument:
heroku git:remote -a [app name] -r [remote]
EDIT: thanks to Алекс...
How can I listen to the form submit event in javascript?
...alidation javascript library and I've been looking on google how to detect if a submit button is clicked but all I found is code where you have to use onClick on onSubmit="function()" in html.
...
Is it valid to replace http:// with // in a ?
...relative URL without a scheme (http: or https:) is valid, per RFC 3986: "Uniform Resource Identifier (URI): Generic Syntax", Section 4.2. If a client chokes on it, then it's the client's fault because they're not complying with the URI syntax specified in the RFC.
Your example is valid and should ...
How to import a module given its name as string?
...e importlib.import_module for Python 2 and and Python 3.
You can use exec if you want to as well.
Or using __import__ you can import a list of modules by doing this:
>>> moduleNames = ['sys', 'os', 're', 'unittest']
>>> moduleNames
['sys', 'os', 're', 'unittest']
>>> m...
How to remove elements from a generic list while iterating over it?
...umerable.Range(1, 10));
for (int i = list.Count - 1; i >= 0; i--)
{
if (list[i] > 5)
list.RemoveAt(i);
}
list.ForEach(i => Console.WriteLine(i));
Alternately, you can use the RemoveAll method with a predicate to test against:
safePendingList.RemoveAll(item => item.Value ==...
What is the difference between Xamarin.Form's LayoutOptions, especially Fill and Expand?
...alignment within its space.
Expand defines whether it occupies more space if available.
Theory
The structure LayoutOptions controls two distinct behaviors:
Alignment: How is the view aligned within the parent view?
Start: For vertical alignment the view is moved to the top. For horizontal ali...
Create instance of generic type whose constructor requires a parameter?
If BaseFruit has a constructor that accepts an int weight , can I instantiate a piece of fruit in a generic method like this?
...
Java 8 forEach with index [duplicate]
...
Would this work in case you want specific order for params (e.g. sorted)?
– Tomer Cagan
Jun 4 '16 at 11:49
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