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How to get a specific output iterating a hash in Ruby?
...
328
hash.each do |key, array|
puts "#{key}-----"
puts array
end
Regarding order I should add...
jQuery map vs. each
...you can potentially waste a lot of memory.
For example:
var items = [1,2,3,4];
$.each(items, function() {
alert('this is ' + this);
});
var newItems = $.map(items, function(i) {
return i + 1;
});
// newItems is [2,3,4,5]
You can also use the map function to remove an item from an array. F...
Backporting Python 3 open(encoding=“utf-8”) to Python 2
I have a Python codebase, built for Python 3, which uses Python 3 style open() with encoding parameter:
6 Answers
...
How does zip(*[iter(s)]*n) work in Python?
... arguments for a function call. Therefore you're passing the same iterator 3 times to zip(), and it pulls an item from the iterator each time.
x = iter([1,2,3,4,5,6,7,8,9])
print zip(x, x, x)
share
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...
Pandas dataframe get first row of each group
...;> df.groupby('id').first()
value
id
1 first
2 first
3 first
4 second
5 first
6 first
7 fourth
If you need id as column:
>>> df.groupby('id').first().reset_index()
id value
0 1 first
1 2 first
2 3 first
3 4 second
4 5 first
5 6...
Integrate ZXing in Android Studio
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234
I was integrating ZXING into an Android application and there were no good sources for the inpu...
Python - abs vs fabs
...(-2))
Out[7]: int
In [8]: type(abs(-2.0))
Out[8]: float
In [9]: type(abs(3+4j))
Out[9]: float
In [10]: type(math.fabs(-2))
Out[10]: float
In [11]: type(math.fabs(-2.0))
Out[11]: float
In [12]: type(math.fabs(3+4j))
---------------------------------------------------------------------------
Type...
Can't install Ruby under Lion with RVM – GCC issues
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553
This answer was edited multiple times and now contains several alternative solutions. Try the...
Remove empty elements from an array in Javascript
... to remove null or undefined values:
var array = [0, 1, null, 2, "", 3, undefined, 3,,,,,, 4,, 4,, 5,, 6,,,,];
var filtered = array.filter(function (el) {
return el != null;
});
console.log(filtered);
It will depend on what you consider to be "empty" for example, if you were d...