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Ruby function to remove all white spaces?
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@joel.neely: I answered this question a long time ago, but read the question again, this time more carefully. The OP asked for "a function to remove all whitespace", but then asked for "something like PHP's trim()". So, it's a bit difficult to know exactly what they w...
Expert R users, what's in your .Rprofile? [closed]
...th multiple monitors
options("digits.secs"=3) # show sub-second time stamps
r <- getOption("repos") # hard code the US repo for CRAN
r["CRAN"] <- "http://cran.us.r-project.org"
options(repos = r)
rm(r)
## put something this is your .Rprofile to customize the defaults
s...
Python to print out status bar and percentage
...ther answers.
A simple example of how to use it:
import progressbar
from time import sleep
bar = progressbar.ProgressBar(maxval=20, \
widgets=[progressbar.Bar('=', '[', ']'), ' ', progressbar.Percentage()])
bar.start()
for i in xrange(20):
bar.update(i+1)
sleep(0.1)
bar.finish()
To i...
Why is Java's Iterator not an Iterable?
...op: inside the loop there is only ever a forward progression one item at a time over the items returned by the iterator.
Also, allowing this would also make it easy to use the for loop for Enumerations, which, as has been pointed out elsewhere, are analogous to Iterators not Iterables.
So don't ma...
PHP date() format when inserting into datetime in MySQL
... date() function in PHP if I want to insert the result into a MySQL datetime type column?
13 Answers
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How to convert String to long in Java?
...(long), as this method is
likely to yield significantly better space and time performance by
caching frequently requested values. Note that unlike the
corresponding method in the Integer class, this method is not required
to cache values within a particular range.
Thanks to auto-unboxing a...
Why is lazy evaluation useful?
...f lazy evaluation, the rest is never sorted, saving a lot of computational time.
This is of course a very simple example, but laziness works in the same way for programs that are very large.
There is, however, a downside to all this: it becomes harder to predict the runtime speed and memory usage ...
Check to see if python script is running
...e condition. If two instances of the script are executed at about the same time, it's possible that if os.path.isfile(pidfile) may evaluate to false for both, causing them to both write the lock file and continue running.
– Cerin
May 10 '13 at 20:05
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How accurate is python's time.sleep()?
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The accuracy of the time.sleep function depends on your underlying OS's sleep accuracy. For non-realtime OS's like a stock Windows the smallest interval you can sleep for is about 10-13ms. I have seen accurate sleeps within several millisecond...
JavaScript: clone a function
...big issue with this answer is that once you bind, you cannot bind a second time. Subsequent calls to apply also ignore the 'this' object passed. Example: var f = function() { console.log('hello ' + this.name) } when bound to {name: 'Bob'} prints 'hello Bob'. f.apply({name: 'Sam'}) will also print...