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How to avoid warning when introducing NAs by coercion
... na = x %in% na.strings
x[na] = 0
x = as.numeric(x)
x[na] = NA_real_
x
}
as.num(c("1", "2", "X"), na.strings="X")
#[1] 1 2 NA
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Contains method for a slice
...re with map[string] struct{}. map[string] struct{} seems like a hack especially initializing an empty struct struct {}{}
– vadasambar
Sep 12 '19 at 12:17
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Can I serve multiple clients using just Flask app.run() as standalone?
... need static files, no HTTP Post methods. My requirement is, I want to run all Flask threads as part of my parent app, so that they all can share variables.
– ATOzTOA
Feb 12 '13 at 6:03
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Fast Linux File Count for a large number of files
...ke a while if there are a lot of them. Also there will be no output until all of the names are read and sorted. Use the ls -f option to turn off sorting.
ls -f | wc -l
Note that this will also enable -a, so ., .., and other files starting with . will be counted.
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Is there a recommended format for multi-line imports?
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Personally I go with parentheses when importing more than one component and sort them alphabetically. Like so:
from Tkinter import (
Button,
Canvas,
DISABLED,
END,
Entry,
Frame,
LEFT,
NORMAL,
RI...
Declaration/definition of variables locations in ObjectiveC?
Ever since starting to work on iOS apps and objective C I've been really puzzled by the different locations where one could be declaring and defining variables. On one hand we have the traditional C approach, on the other we have the new ObjectiveC directives that add OO on top of that. Could you fo...
How to use php serialize() and unserialize()
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echo json_encode($array); How exactly you pass it depends on the circumstances. Don't get too hung up on that.
– deceze♦
Dec 27 '11 at 7:57
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What is function overloading and overriding in php?
...that method.
In PHP, you can only overload methods using the magic method __call.
An example of overriding:
<?php
class Foo {
function myFoo() {
return "Foo";
}
}
class Bar extends Foo {
function myFoo() {
return "Bar";
}
}
$foo = new Foo;
$bar = new Bar;
echo($foo-&...
C# Linq Group By on multiple columns [duplicate]
...perties in the group by, is there a cleaner way of doing this then listing all the properties?
– guiomie
Aug 21 '15 at 18:35
2
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When to use reinterpret_cast?
...time hence the word static . This is the cast the C++ compiler uses internally for implicit casts also.
11 Answers
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