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Python nested functions variable scoping [duplicate]
...the statement b = 4 commented out, this code outputs 0 1, just what you'd expect.
But if you uncomment that line, on the line print b, you get the error
UnboundLocalError: local variable 'b' referenced before assignment
It seems mysterious that the presence of b = 4 might somehow make b disappea...
How to check if all list items have the same value and return it, or return an “otherValue” if they
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var val = yyy.First().Value;
return yyy.All(x=>x.Value == val) ? val : otherValue;
Cleanest way I can think of. You can make it a one-liner by inlining val, but First() would be evaluated n times, doubling execution time.
To incorporate the "empty set" behavior ...
rgdal package installation
The issue here is not exactly how to plot maps through R, as I have found already a pretty nice example here , but rather how to make it work. In fact, I am unable to load library rgdal :
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What is the string concatenation operator in Oracle?
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It is ||, for example:
select 'Mr ' || ename from emp;
The only "interesting" feature I can think of is that 'x' || null returns 'x', not null as you might perhaps expect.
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Getting a better understanding of callback functions in JavaScript
...and passing in a function to another function as a callback and having it execute, but I'm not understanding the best implementation to do that. I'm looking for a very basic example, like this:
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Is there an easy way to pickle a python function (or otherwise serialize its code)?
...hich can then be reassembled into a function. ie:
import marshal
def foo(x): return x*x
code_string = marshal.dumps(foo.func_code)
Then in the remote process (after transferring code_string):
import marshal, types
code = marshal.loads(code_string)
func = types.FunctionType(code, globals(), "so...
How to take all but the last element in a sequence using LINQ?
...e;
T item = default(T);
do {
hasRemainingItems = it.MoveNext();
if (hasRemainingItems) {
if (!isFirst) yield return item;
item = it.Current;
isFirst = false;
}
} while (hasRemainingItems);
}
static void Main(string[] args) {
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Logical XOR operator in C++?
...sarily do what you might want for non-booleans. And as this is C++, there exists a real bool type instead of having to use int for that purpose.
– Greg Hewgill
Oct 20 '09 at 21:19
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Convert light frequency to RGB?
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Here's a detailed explanation of the entire conversion process: http://www.fourmilab.ch/documents/specrend/. Source code included!
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imp...
object==null or null==object?
... left side of == isn't really useful in Java since Java requires that the expression in an if evaluate to a boolean value, so unless the constant is a boolean, you'd get a compilation error either way you put the arguments. (and if it is a boolean, you shouldn't be using == anyway...)
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