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Why does the order of the loops affect performance when iterating over a 2D array?
... x[1][0] etc...
Meaning that you're hitting them all in order. Now look at the 1st version. You're doing:
x[0][0]
x[1][0]
x[2][0]
x[0][1]
x[1][...
How can I find the number of days between two Date objects in Ruby?
...conds, such as this example
2.0.0-p195 :017 > a_date_time = DateTime.now
=> #<DateTime: 2013-12-31T12:23:03-08:00 ((2456658j,73383s,725757000n),-28800s,2299161j)>
2.0.0-p195 :018 > b_date_time = DateTime.now-20
=> #<DateTime: 2013-12-11T12:23:06-08:00 ((2456638j,73386s,699...
What is the difference between google tag manager and google analytics?
... they used, which pages were the most popular, etc. The only way it can know this stuff is if you put a "tag" on all of your pages. The tag is the javascript code on your pages that runs on the visitor's browser, which tells Google Analytics' servers that they are visiting the page right now.
Th...
What is std::string::c_str() lifetime?
...use the strings are not modified while in that scope. (However, we don't know what use_foo() or ~Foo() might be doing with those values; if they copy the strings elsewhere, then they should do a true copy, and not just copy the char pointers.)
...
How to remove application from app listings on Android Developer Console
...e that new version before publishing it.
A reference
Update, 2016
you can now filter out unpublished or draft apps from your listing.
Unpublish option can be found in the header area, beside PUBLISHED text.
UPDATE 2020
Due to changes in the new play console, the unpublish option was moved to a ...
Android studio using > 100% CPU at all times - no background processes appear to be running
...S seemed to have a HUGE impact toward the high cpu usage - it was 150% and now it's 20%, more or less.
I'm on OS X
Go to: Preferences > Version Control > Background. Now listed under 'Background Operations' are 6 options.
I disabled the first three options which are:
Perform update on VC...
Why is a combiner needed for reduce method that converts type in java 8
...s processed by its own thread in the sequential fashion I described above. Now, if we have N threads, we have N intermediate results. These need to be reduced down to one result. Since each intermediate result is of type T, and we have several, we can use the same accumulator function to reduce thos...
Sample random rows in dataframe
... sample_frac) have been superseded by slice_sample, though they remain for now.
– Matt_B
Sep 4 at 2:50
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Update Git submodule to latest commit on origin
...git submodule init
# Time passes, submodule upstream is updated
# and you now want to update
# Change to the submodule directory
cd submodule_dir
# Checkout desired branch
git checkout master
# Update
git pull
# Get back to your project root
cd ..
# Now the submodules are in the state you want...
When should I use the Visitor Design Pattern? [closed]
...
(Suppose it is a complex hierarchy with a well-established interface.)
Now we want to add a new operation to the hierarchy, namely we want each animal to make its sound. As far as the hierarchy is this simple, you can do it with straight polymorphism:
class Animal
{ public: virtual void makeSou...