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In Python, how do I index a list with another list?
...ng, either by integer, slice or index-list:
class Flexlist(list):
def __getitem__(self, keys):
if isinstance(keys, (int, slice)): return list.__getitem__(self, keys)
return [self[k] for k in keys]
Which, for your example, you would use as:
L = Flexlist(['a', 'b', 'c', 'd', 'e...
What is the difference between quiet NaN and signaling NaN?
...+ in this answer instead of C because it offers the convenient std::numeric_limits::quiet_NaN and std::numeric_limits::signaling_NaN which I could not find in C conveniently.
I could not however find a function to classify if a NaN is sNaN or qNaN, so let's just print out the NaN raw bytes:
main.c...
How to iterate for loop in reverse order in swift?
... an array with one trillion Ints!
Test:
var count = 0
for i in lazy(1...1_000_000_000_000).reverse() {
if ++count > 5 {
break
}
println(i)
}
For Swift 2.0 in Xcode 7:
for i in (1...10).reverse() {
print(i)
}
Note that in Swift 2.0, (1...1_000_000_000_000).reverse(...
undefined reference to `__android_log_print'
...
Try the following in your Android.mk file:
LOCAL_LDLIBS := -L$(SYSROOT)/usr/lib -llog
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How to get Linux console window width in Python
...
rows, columns = subprocess.check_output(['stty', 'size']).split() is a little shorter, plus subprocess is the future
– cdosborn
Mar 17 '15 at 2:00
...
Javascript regex returning true.. then false.. then true.. etc [duplicate]
...
/^[^-_]([a-z0-9-_]{4,20})[^-_]$/gi;
You're using a g (global) RegExp. In JavaScript, global regexen have state: you call them (with exec, test etc.) the first time, you get the first match in a given string. Call them again and ...
How do I create an average from a Ruby array?
...
Try this:
arr = [5, 6, 7, 8]
arr.inject{ |sum, el| sum + el }.to_f / arr.size
=> 6.5
Note the .to_f, which you'll want for avoiding any problems from integer division. You can also do:
arr = [5, 6, 7, 8]
arr.inject(0.0) { |sum, el| sum + el } / arr.size
=> 6.5
You can define it...
How to open a new window on form submit
...
No need for Javascript, you just have to add a target="_blank" attribute in your form tag.
<form target="_blank" action="http://example.com"
method="post" id="mc-embedded-subscribe-form"
name="mc-embedded-subscribe-form" class="validate"
>
...
JavaScript Regular Expression Email Validation [duplicate]
...ernatively, define it as a regular expression:
var pattern = /^\w+@[a-zA-Z_]+?\.[a-zA-Z]{2,3}$/;
BTW, please don't validate email addresses on the client-side. Your regular expression is way too simple to pass for a solid implementation anyway.
See the real thing here: http://www.ex-parrot.co...
What are the applications of binary trees?
...oving from one level to the next requires one comparison, and there are log_2(m) levels, for a total of log_2(m) comparisons.
In contrast, an n-ary tree will require log_2(n) comparisons (using a binary search) to move to the next level. Since there are log_n(m) total levels, the search will requi...