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What's the safest way to iterate through the keys of a Perl hash?
... of uppercase keys with doubled values works fine using keys():
%h = (a => 1, b => 2);
foreach my $k (keys %h)
{
$h{uc $k} = $h{$k} * 2;
}
producing the expected resulting hash:
(a => 1, A => 2, b => 2, B => 4)
But using each() to do the same thing:
%h = (a => 1, b =&g...
How can I install a .ipa file to my iPhone simulator
...at application to my iPhone simulators applications folder found at:
HD
> Applications
> Xcode.app (right click - Show Package Contents)
> Contents
> Developer
> Platforms
> iPhoneSimulator.platform
> SDKs
> iPhoneSimulator6.0.sdk
> Applications
Hope this helps!
(Note:...
What's wrong with using == to compare floats in Java?
...test floats for 'equality' is:
if(Math.abs(sectionID - currentSectionID) < epsilon)
where epsilon is a very small number like 0.00000001, depending on the desired precision.
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How to call methods dynamically based on their name? [duplicate]
...e
def bar(*args); end
end
obj = MyClass.new
eval
eval('obj.foo') #=> nil
eval('obj.bar') #=> NoMethodError: private method `bar' called
# With arguments:
eval('obj.foo(:arg1, :arg2)') #=> nil
eval('obj.bar(:arg1, :arg2)') #=> NoMethodError: private method `bar' called
instance_...
Why is early return slower than else?
... results, without_else() is repeatedly slightly slower than with_else():
>>> T(lambda : without_else()).repeat()
[0.42015745017874906, 0.3188967452567226, 0.31984281521812363]
>>> T(lambda : with_else()).repeat()
[0.36009842032996175, 0.28962249392031936, 0.2927151355828528]
>&...
How to sort a list of lists by a specific index of the inner list?
...
This is a job for itemgetter
>>> from operator import itemgetter
>>> L=[[0, 1, 'f'], [4, 2, 't'], [9, 4, 'afsd']]
>>> sorted(L, key=itemgetter(2))
[[9, 4, 'afsd'], [0, 1, 'f'], [4, 2, 't']]
It is also possible to use a lambda ...
array_push() with key value pair
...
If you need to add multiple key=>value, then try this.
$data = array_merge($data, array("cat"=>"wagon","foo"=>"baar"));
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How to make a .jar out from an Android Studio project
...d)
Expand gradle panel from right and open all tasks under yourlibrary->others. You will see two new tasks there -- createJar and deleteJar
Double click on createJar
Once the task run successfully, get your generated jar from path mentioned in createJar task i.e. libs/xxxx.jar
copy the newl...
How to alias a table in Laravel Eloquent queries (or using Query Builder)?
...th AS. Try
$users = DB::table('really_long_table_name AS t')
->select('t.id AS uid')
->get();
Let's see it in action with an awesome tinker tool
$ php artisan tinker
[1] > Schema::create('really_long_table_name', function($table) {$table->increments('id');});
/...
Python convert tuple to string
...
Use str.join:
>>> tup = ('a', 'b', 'c', 'd', 'g', 'x', 'r', 'e')
>>> ''.join(tup)
'abcdgxre'
>>>
>>> help(str.join)
Help on method_descriptor:
join(...)
S.join(iterable) -> str
Return a strin...