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How to organize large R programs?
...bare bones first package: hilaryparker.com/2014/04/29/writing-an-r-package-from-scratch
– panterasBox
Sep 3 '15 at 14:32
1
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What's better at freeing memory with PHP: unset() or $var = null
...a. You might get memory freed / shrunk faster, but it may steal CPU cycles from the code that truly needs them sooner, resulting in a longer overall execution time.
(Since 2013, that unset man page don't include that section anymore)
Note that until php5.3, if you have two objects in circular refer...
How to change cursor from pointer to finger using jQuery?
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Post as a guest
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Check whether a string is not null and not empty
... && fails, thus ensuring you will not get a null pointer exception from str.isEmpty() if str is null.
Beware, it's only available since Java SE 1.6. You have to check str.length() == 0 on previous versions.
To ignore whitespace as well:
if(str != null && !str.trim().isEmpty())
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Why must wait() always be in synchronized block
...s true:
You can get spurious wakeups (meaning that a thread can wake up from waiting without ever having received a notification), or
The condition can get set, but a third thread makes the condition false again by the time the waiting thread wakes up (and reacquires the monitor).
To deal wit...
What is a patch in git version control?
...ntrol so I am trying to figure out what a patch is and how is it different from the rest of activities I do in git?
5 Answe...
Converting JSON String to Dictionary Not List
...nts, and then adding [0] on the end of it will take just the first element from that resulting list slice. What you need to use to get the result you want is a list comprehension:
[p[0] for p in datapoints[0:5]]
Here's a simple way to calculate the mean:
sum(p[0] for p in datapoints[0:5])/5. # R...
Why should I use Hamcrest-Matcher and assertThat() instead of traditional assertXXX()-Methods
...easier to read, but once the assert fails, you'll get a good error message from assertThat, but only a very minimal amount of information from assertTrue.
assertThat will tell you what the assertion was and what you got instead. assertTrue will only tell you that you got false where you expected tr...
Creating java date object from year,month,day
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Beware, the months used to be numbered from zero in Java 7. Use constants to avoid trouble.
– jediz
Jun 6 '18 at 9:31
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Gmail's new image caching is breaking image links in newsletter
...t the gmail server GoogleImageProxy will try to fetch and store the images from your site to its own proxy server. while fetching the images, GoogleImageProxy found some 404 statuses against your missing images and 403 against some protected images. GoogleImagesProxy has stored these statuses into i...