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How to calculate the time interval between two time strings
...statistics mean and variance functions work directly with timedelta object now? Any thought on that? Also, any help to compute the variance of timedelta objects will be useful.
– CKM
Feb 9 '17 at 10:04
...
How do I launch the Android emulator from the command line?
...om the terminal. I have successfully created the HelloWorld project and now I'm trying to run it from the command line in the Android emulator. Which command runs the emulator for my HelloWorld project?
...
Sending a message to nil in Objective-C
...ize(); ++i){
System.out.println(list.get(i).toString());
}
}
Now, if you call that method like so: someObject.foo(NULL); you're going to probably get a NullPointerException when it tries to access list, in this case in the call to list.size(); Now, you'd probably never call someObject....
What is “loose coupling?” Please provide examples
...n to keep track of the items we'd have to change the Order class as well.
Now here's a slightly better way to do the same thing:
Less Coupled Example:
public class CartEntry
{
public float Price;
public int Quantity;
public float GetLineItemTotal()
{
return Price * Quanti...
How do I merge two dictionaries in a single expression in Python (taking union of dictionaries)?
...# modifies z with y's keys and values & returns None
return z
and now:
z = merge_two_dicts(x, y)
In Python 3.9.0a4 or greater (final release date approx October 2020): PEP-584, discussed here, was implemented to further simplify this:
z = x | y # NOTE: 3.9+ ONLY
Explanation
Sa...
String is immutable. What exactly is the meaning? [duplicate]
...efore coming to any conclusion.
This is how String works:
String str = "knowledge";
This, as usual, creates a string containing "knowledge" and assigns it a reference str. Simple enough? Lets perform some more functions:
String s = str; // assigns a new reference to the same string "knowle...
What is the curiously recurring template pattern (CRTP)?
...ss A : public X<A> {...};
It is curiously recurring, isn't it? :)
Now, what does this give you? This actually gives the X template the ability to be a base class for its specializations.
For example, you could make a generic singleton class (simplified version) like this
template <cl...
Convert a list to a data frame
...
Update July 2020:
The default for the parameter stringsAsFactors is now default.stringsAsFactors() which in turn yields FALSE as its default.
Assuming your list of lists is called l:
df <- data.frame(matrix(unlist(l), nrow=length(l), byrow=T))
The above will convert all character columns...
The entity type is not part of the model for the current context
...
Thanks, Dan - this fixes it. Now the tables are created. There is no other way around, EF can not do this on its own? I cant just annotate the entity with [ToTable('Estates')] or something like that?
– janhartmann
D...
Installing vim with ruby support (+ruby)
...
I think "Compiling Vim With Ruby Integration On Snow Leopard" might actually help. I'm on exactly same boat at the moment.
Ok... got it to work. Took me like half hour or so.
This should help (I got Ubuntu):
sudo apt-get install mercurial
hg clone https://vim.googlecod...