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What is the difference between Python's list methods append and extend?
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append: Appends object at the end.
x = [1, 2, 3]
x.append([4, 5])
print (x)
gives you: [1, 2, 3, [4, 5]]
extend: Extends list by appending elements from the iterable.
x = [1, 2, 3]
x.extend([4, 5])
print (x)
gives you: [1, 2, 3, 4, 5]
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Hiding elements in responsive layout?
...hone, .hidden-tablet etc. are unsupported/obsolete.
UPDATE:
In Bootstrap 4 there are 2 types of classes:
The hidden-*-up which hide the element when the viewport is at the given breakpoint or wider.
hidden-*-down which hide the element when the viewport is at the given breakpoint or smaller.
A...
How can I check the system version of Android?
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424
Check android.os.Build.VERSION.
CODENAME: The current development codename, or the stri...
How to validate date with format “mm/dd/yyyy” in JavaScript?
...tring)
{
// First check for the pattern
if(!/^\d{1,2}\/\d{1,2}\/\d{4}$/.test(dateString))
return false;
// Parse the date parts to integers
var parts = dateString.split("/");
var day = parseInt(parts[1], 10);
var month = parseInt(parts[0], 10);
var year = parseIn...
Bash: Copy named files recursively, preserving folder structure
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154
Have you tried using the --parents option? I don't know if OS X supports that, but that works on...
How to remove an item from an array in AngularJS scope?
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answered Jan 10 '13 at 4:11
Josh David MillerJosh David Miller
120k1616 gold badges123123 silver badges9494 bronze badges
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How to delete multiple values from a vector?
...e (1 : 10)
> remove <- c (2, 3, 5)
> a
[1] 10 5 2 7 1 6 3 4 8 9
> a %in% remove
[1] FALSE TRUE TRUE FALSE FALSE FALSE TRUE FALSE FALSE FALSE
> a [! a %in% remove]
[1] 10 7 1 6 4 8 9
Note that this will silently remove incomparables (stuff like NA or Inf) as well...
git + LaTeX workflow
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abcdabcd
39.4k77 gold badges6969 silver badges9696 bronze badges
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How do exceptions work (behind the scenes) in c++
...}
catch (const MyException& e)
{
log(3);
}
log(4);
}
I compiled it with g++ -m32 -W -Wall -O3 -save-temps -c, and looked at the generated assembly file.
.file "foo.cpp"
.section .text._ZN11MyExceptionD1Ev,"axG",@progbits,_ZN11MyExceptionD1Ev,comdat
.al...
Using 'return' in a Ruby block
...value = block.call
irb(main):003:1> puts "value=#{value}"
irb(main):004:1> end
=> nil
irb(main):005:0>
irb(main):006:0* thing {
irb(main):007:1* return 6 * 7
irb(main):008:1> }
LocalJumpError: unexpected return
from (irb):7:in `block in irb_binding'
from (irb):2:in...