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How to organize large R programs?
...
If you're growing your source-tree/analysis "organically," don't you find this hard to do/cumbersome? If you notice a mistake in your code (common while exploring a new problem space), you have to (i) fix source; (ii) reinstall package; (iii) reload it into your workspace? I...
How do you loop through each line in a text file using a windows batch file?
...stead of % : (Type help for)
for /F "tokens=1,2,3" %%i in (myfile.txt) do call :process %%i %%j %%k
goto thenextstep
:process
set VAR1=%1
set VAR2=%2
set VAR3=%3
COMMANDS TO PROCESS INFORMATION
goto :EOF
What this does:
The "do call :process %%i %%j %%k" at the end of the for command passes the i...
Constructor of an abstract class in C#
...bstract class. That way you can have classes that inherit from that class call the base constructor.
public abstract class A{
private string data;
protected A(string myString){
data = myString;
}
}
public class B : A {
B(string myString) : base(myString){}
}
...
How come a non-const reference cannot bind to a temporary object?
... C++ doesn't want you to accidentally
modify temporaries, but directly
calling a non-const member function on
a modifiable rvalue is explicit, so
it's allowed ...
Basically, you shouldn't try to modify temporaries for the very reason that they are temporary objects and will die any moment ...
Get type of all variables
...n R variable is written to disk, the data layout changes yet again, and is called the data's storage.mode. The function storage.mode(...) reveals this low level information: see Mode, Class, and Type of R objects. You shouldn't need to worry about R's storage.mode unless you are trying to understan...
Is there a way to provide named parameters in a function call in JavaScript?
...structuring can be used to simulate named parameters. It would require the caller to pass an object, but you can avoid all of the checks inside the function if you also use default parameters:
myFunction({ param1 : 70, param2 : 175});
function myFunction({param1, param2}={}){
// ...function body...
How to set a Django model field's default value to a function call / callable (e.g., a date relative
...n to create a field in the class.
PRE Django 1.7
Django lets you pass a callable as the default, and it will invoke it each time, just as you want:
from datetime import datetime, timedelta
class MyModel(models.Model):
# default to 1 day from now
my_date = models.DateTimeField(default=lambda:...
What do all of Scala's symbolic operators mean?
...ose of teaching, into four categories:
Keywords/reserved symbols
Automatically imported methods
Common methods
Syntactic sugars/composition
It is fortunate, then, that most categories are represented in the question:
-> // Automatically imported method
||= // Syntactic sugar
++= // Sy...
Can I find out the return value before returning while debugging in Visual Studio?
...us the easiest way to access it is by putting a breakpoint on the function call and step over (F10) the call.
Update for VS2015: boo! unfortunately, it doesn't appear to be in VS2015 (devenv v14)
Update for VS2017: it's back. (devenv v15)
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How can I find script's directory with Python? [duplicate]
...
You need to call os.path.realpath on __file__, so that when __file__ is a filename without the path you still get the dir path:
import os
print(os.path.dirname(os.path.realpath(__file__)))
...