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Difference between Inheritance and Composition
...rectly), and could lead to some confusion.
Interface implementation is a form of inheritance... when you implement an interface, you're not only inheriting all the constants, you are committing your object to be of the type specified by the interface; it's still an "is-a" relationship. If a car im...
RequestDispatcher.forward() vs HttpServletResponse.sendRedirect()
...tcher("/WEB-INF/login.jsp").forward(request, response);
When you submit a form, you normally want to use POST:
<form action="login" method="post">
This way the servlet's doPost() will be invoked and you can do any postprocessing stuff in there (e.g. validation, business logic, login the user...
How to check if an object is nullable?
...s question has already been answered long ago.
To check if a type is some form of Nullable<> using reflection, you first have to convert your constructed generic type, for example Nullable<int>, into the generic type definition, Nullable<>. You can do that by using the GetGenericT...
Converting a column within pandas dataframe from int to string
...() and apply() ) do not preserve NULL values in either the nan or the None form.
import pandas as pd
import numpy as np
df = pd.DataFrame([None,'string',np.nan,42], index=[0,1,2,3], columns=['A'])
df1 = df['A'].astype(str)
df2 = df['A'].apply(str)
print df.isnull()
print df1.isnull()
print df2....
Why are floating point numbers inaccurate?
...ore detail, see: 675539944105574 / 4503599627370496.)
Now that we've transformed the third component into a fractional number, adding 1 gives the true mantissa.
Recapping the Components
Sign (first component): 0 for positive, 1 for negative
Exponent (middle component): Subtract 2(# of bits) - 1 ...
Is there an equivalent for var_dump (PHP) in Javascript?
... of console.debug(object) before today, and it saved me a ton of time on a form I've been struggling with for three days. Withing 20 minutes, I had it fixed. Thank you!
– ShiningLight
Feb 27 '15 at 19:48
...
Pandas percentage of total with groupby
...703
Name: count, dtype: float64
For multiple groups you have to use transform (using Radical's df):
In [21]: c = df.groupby(["Group 1","Group 2","Final Group"])["Numbers I want as percents"].sum().rename("count")
In [22]: c / c.groupby(level=[0, 1]).transform("sum")
Out[22]:
Group 1 Group 2 F...
Logging raw HTTP request/response in ASP.NET MVC & IIS7
... the requests and response in as close as possible to the raw, on-the-wire format (i.e including HTTP method, path, all headers, and the body) into a database.
...
Sorting dropdown alphabetically in AngularJS
...xchange.using('gps', function() { StackExchange.gps.track('embedded_signup_form.view', { location: 'question_page' }); });
$window.unbind('scroll', onScroll);
}
};
...
How to get the number of Characters in a String?
...unes.
For example, an 'e' and '◌́◌́' (acute "\u0301") can combine to form 'é' ("e\u0301" in NFD). Together these two runes are one character.
The definition of a character may vary depending on the application.
For normalization we will define it as:
a sequence of runes that starts with ...