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How do I check whether a file exists without exceptions?
..._it(), it's safer to use a try around the attempt to open it. Checking and then opening risks the file being deleted or moved or something between when you check and when you try to open it.
If you're not planning to open the file immediately, you can use os.path.isfile
Return True if path is a...
INSTALL_FAILED_UPDATE_INCOMPATIBLE when I try to install compiled .apk on device
...t installed for this user"
We have to uninstall manually for all users!, then we can install our compiled application with no problems.
Another options:
Remove the old application and install again.
Use Android Debug Bridge command:
adb uninstall [PACKAGE NAME]
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How do I remove an array item in TypeScript?
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If array is type of objects, then the simplest way is
let foo_object // Item to remove
this.foo_objects = this.foo_objects.filter(obj => obj !== foo_object);
share
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Should I learn C before learning C++? [closed]
...ether or not you started with C or started with C++.
If you know C first, then that is good plus to learning C++. You will start with knowing a chunk of the language. If you do not know C first then there is no point focusing on a different language. There are plenty of good books and tutorials ...
How do I add an icon to a mingw-gcc compiled executable?
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You need to create the icon first. Then you need to create a RC file with the below content. Here we'll name it as my.rc.
id ICON "path/to/my.ico"
The id mentioned in the above command can be pretty much anything. It doesn't matter unless you want to refer ...
Should I instantiate instance variables on declaration or in the constructor?
...iable with a value that is not used (for example declare and init vars and then throw an exception before half of those vars needed to have a value). You also do not wind up doing pointless initialization (like int i = 0; and then later on, before "i" is used, do i = 5;.
I value consistency very m...
Controlling number of decimal digits in print output in R
...istical tests that rely on differences beyond the 15th significant figure, then your analysis is almost certainly junk.
On the other hand, if you are just dealing with very small numbers, that is less of a problem, since R can handle number as small as .Machine$double.xmin (usually 2e-308).
Compar...
How do I create a constant in Python?
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Rather then do what is in "Constants in Python," you should use the "property" function or decorator.
– Seth Johnson
Apr 21 '10 at 21:30
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Is SHA-1 secure for password storage?
...all extra cost per password.
If the pre-computed table is a rainbow table, then N can be somewhat bigger, because storage cost is reduced. The bottleneck on N becomes the CPU power that the attacker can muster, not the size of his harddisks.
If N is large enough that the CPU-cost of hashing N pass...
How to exit from PostgreSQL command line utility: psql
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Type \q and then press ENTER to quit psql.
UPDATE: 19-OCT-2018
As of PostgreSQL 11, the keywords "quit" and "exit" in the PostgreSQL command-line interface have been included to help make it easier to leave the command-line tool.
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