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Just what is an IntPtr exactly?
...IntPtr type; every time it has needed to be used I have simply put null or IntPtr.Zero and found most functions to work. What exactly is it and when/why is it used?
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Change column type from string to float in Pandas
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You have four main options for converting types in pandas:
to_numeric() - provides functionality to safely convert non-numeric types (e.g. strings) to a suitable numeric type. (See also to_datetime() and to_timedelta().)
astype() - convert (almost) an...
Running shell command and capturing the output
... shell command and return its output as a string , no matter, is it an error or success message. I just want to get the same result that I would have gotten with the command line.
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What is SaaS, PaaS and IaaS? With examples
... as the name suggests, provides you the computing infrastructure, physical or (quite often) virtual machines and other resources like virtual-machine disk image library, block and file-based storage, firewalls, load balancers, IP addresses, virtual local area networks etc.
Examples: Amazon EC2, Wi...
When do items in HTML5 local storage expire?
For how long is data stored in localStorage (as part of DOM Storage in HTML5) available? Can I set an expiration time for the data which I put into local storage?
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Singleton pattern in nodejs - is it needed?
...has basically to do with nodejs caching. Plain and simple.
https://nodejs.org/api/modules.html#modules_caching
(v 6.3.1)
Caching
Modules are cached after the first time they are loaded. This means
(among other things) that every call to require('foo') will get
exactly the same object ...
How to get year, month, day, hours, minutes, seconds and milliseconds of the current moment in Java?
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You can use the getters of java.time.LocalDateTime for that.
LocalDateTime now = LocalDateTime.now();
int year = now.getYear();
int month = now.getMonthValue();
int day = now.getDayOfMonth();
int hour = now.getHour();
int minute = now.getMinute();
int second = now.getSecond();...
What is the difference between a symbolic link and a hard link?
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Underneath the file system, files are represented by inodes. (Or is it multiple inodes? Not sure.)
A file in the file system is basically a link to an inode.
A hard link, then, just creates another file with a link to the same underlying inode.
When you delete a file, it removes one ...
PHP script - detect whether running under linux or Windows?
I have a PHP script that may be placed on a windows system or a linux system. I need to run different commands in either case.
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Why use getters and setters/accessors?
...d setters - that only get and set - instead of simply using public fields for those variables?
38 Answers
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