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How to apply a function to two columns of Pandas dataframe
Suppose I have a df which has columns of 'ID', 'col_1', 'col_2' . And I define a function :
12 Answers
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Python pandas: fill a dataframe row by row
...you want to align the input (for example you then don't have to to specify all of the elements)
In [7]: df = pandas.DataFrame(columns=['a','b','c','d'], index=['x','y','z'])
In [8]: df.loc['y'] = pandas.Series({'a':1, 'b':5, 'c':2, 'd':3})
In [9]: df
Out[9]:
a b c d
x NaN NaN Na...
How to make return key on iPhone make keyboard disappear?
...ate after you init the textfield in the .m:
yourTextField = [[UITextField alloc] initWithFrame:yourFrame];
//....
//....
//Setting the textField's properties
//....
//The next line is important!!
yourTextField.delegate = self; //self references the viewcontroller or view your textField is on
...
How can I create an object and add attributes to it?
...ant to make a "bunch class", a very simple one already exists in Python -- all functions can have arbitrary attributes (including lambda functions). So, the following works:
obj = someobject
obj.a = lambda: None
setattr(obj.a, 'somefield', 'somevalue')
Whether the loss of clarity compared to the...
Static variables in JavaScript
...
If you come from a class-based, statically typed object-oriented language (like Java, C++ or C#) I assume that you are trying to create a variable or method associated to a "type" but not to an instance.
An example using a "classical" approach, with constructor ...
Block Comments in a Shell Script
...ommands and noh is for nohighlight. Search term highlighting will automatically resume the next time you search for something. Example: :10,100s/^/#/g|noh
– Matthew
Mar 13 '15 at 20:43
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Is it a good practice to use an empty URL for a HTML form's action attribute? (action=“”)
...for compatibility with legacy content. [RFC3986]
This definitely works in all current browsers, but may not work as expected in some older browsers ("browsers do weird things with an empty action="" attribute"), which is why the spec strongly discourages authors from leaving it empty:
The action a...
Ensure that HttpConfiguration.EnsureInitialized()
I've installed Visual Studio 2013 and when I run my app I get the error below.
14 Answers
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How do I get around type erasure on Scala? Or, why can't I get the type parameter of my collections?
...hese instances are objects, you can pass them around, store them, and generally call methods on them. With the support of implicit parameters, it becomes a very powerful tool. Take the following example, for instance:
object Registry {
import scala.reflect.Manifest
private var map= Map.empty[...
Python dictionary: Get list of values for list of keys
...n list-comp:
Build list and throw exception if key not found: map(mydict.__getitem__, mykeys)
Build list with None if key not found: map(mydict.get, mykeys)
Alternatively, using operator.itemgetter can return a tuple:
from operator import itemgetter
myvalues = itemgetter(*mykeys)(mydict)
# use ...