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Changing one character in a string
...e unicode capable applications in C. But you have to care about it all the time and need to test it explicitly to avoid trouble. Everything is machine-oriented. I worked with PHP before learning Python, and that language is a total mess. Regarding your note on fast CPUs I'm totally with you. But a p...
How to split text without spaces into list of words?
... very bad.
Optimization
The implementation consumes a linear amount of time and memory, so it is reasonably efficient. If you need further speedups, you can build a suffix tree from the word list to reduce the size of the set of candidates.
If you need to process a very large consecutive string...
When should I use double or single quotes in JavaScript?
..."');
alert("Say 'Hello'");
This can get complicated:
alert("It's \"game\" time.");
alert('It\'s "game" time.');
Another option, new in ECMAScript 6, is template literals which use the backtick character:
alert(`Use "double" and 'single' quotes in the same string`);
alert(`Escape the \` back-tick ...
Replace console output in Python
...rrent iteration and total iterations as a progression bar with an expected time of finishing. Super useful and quick. Works for python2 and python3.
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What to do Regular expression pattern doesn't match anywhere in string?
...t_tags)
{
my $hash_ref = {};
# Now extract each of the fields one at a time.
($hash_ref->{"name"}) = $input_tag =~ /name="([^"]*)"/;
($hash_ref->{"value"}) = $input_tag =~ /value="([^"]*)"/;
# Put $hash_ref in a list or something, or otherwise process it
}
The basic principle her...
Convert timestamp in milliseconds to string formatted time in Java
... long value ( number of milliseconds elapsed from 1/1/1970 i.e. Epoch ) to time of format h:m:s:ms .
9 Answers
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What does an exclamation mark mean in the Swift language?
...ays:
"forced unwrapping": john! (gives the Person value if it exists, runtime error if it is nil)
"optional binding": if let p = john { println(p) } (executes the println if the value exists)
"optional chaining": john?.learnAboutSwift() (executes this made-up method if the value exists)
I guess ...
How can I replace a newline (\n) using sed?
...stitute, /\n/ regex for new line, / / by a space, /g global match (as many times as it can)
sed will loop through step 1 to 3 until it reach the last line, getting all lines fit in the pattern space where sed will substitute all \n characters
Alternatives
All alternatives, unlike sed will not need...
Difference between as.POSIXct/as.POSIXlt and strptime for converting character vectors to POSIXct/PO
... of questions here that asks about how to convert character vectors to datetime classes. I often see 2 methods, the strptime and the as.POSIXct/as.POSIXlt methods. I looked at the 2 functions but am unclear what the difference is.
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Python date string to date object
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You can use strptime in the datetime package of Python:
>>> import datetime
>>> datetime.datetime.strptime('24052010', "%d%m%Y").date()
datetime.date(2010, 5, 24)
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