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How to see if an object is an array without using reflection?
...ference type. See JLS 4.10.3.
Therefore, the following is incorrect as a test to see if obj is an array of any kind:
// INCORRECT!
public boolean isArray(final Object obj) {
return obj instanceof Object[];
}
Specifically, it doesn't work if obj is 1-D array of primitives. (It does work for...
Delete with Join in MySQL
...table, you must use the alias when referring to the table: DELETE t1 FROM test AS t1, test2 WHERE ..." so using an alias is fine.
– Peter Bowers
Feb 25 '15 at 7:26
add a comm...
UITextView that expands to text using auto layout
...cMetric; } return size; }. Tell me if it's working for you. Didn't test it myself.
– manuelwaldner
Mar 14 '17 at 8:27
...
What is the most efficient way of finding all the factors of a number in Python?
...ad from this alteration may cause the function to take longer.
I ran some tests in order to check the speed. Below is the code used. To produce the different plots, I altered the X = range(1,100,1) accordingly.
import timeit
from math import sqrt
from matplotlib.pyplot import plot, legend, show
d...
Regex Pattern to Match, Excluding when… / Except between
...when there are certain other (could be any number) patterns present in the test string. Fortunately, you can take advantage of your programming language: keep the regexes simple and just use a compound conditional. A best practice would be to capture this idea in a reusable component, so let's creat...
Select multiple records based on list of Id's with linq
... .Contains took 2 minutes and 19 seconds! I used pure IEnumerable for this testing to prove my statement. If you use List instead of IEnumerable, .Where and .Contains will be faster. Anyway the difference is significant. The fastest .Where .Contains is with Set<>. All it depends on complexity ...
What is the difference between mutex and critical section?
...cond. A critical section takes ~50 ms for 1,000,000 acquires.
Here's the test code, I ran this and got similar results if mutex is first or second, so we aren't seeing any other effects.
HANDLE mutex = CreateMutex(NULL, FALSE, NULL);
CRITICAL_SECTION critSec;
InitializeCriticalSection(&critSe...
Apply multiple functions to multiple groupby columns
...
@slackline yes. i just tested it and it works fine. Ted must have just created the frame a few different times and since it was created via random number generation, the df data to actually generate the data was different than the one ultimately us...
Automatic Preferred Max Layout Width is not available on iOS versions prior to 8.0
...
@CharlesA. I've been testing with an empty project and found another label attribute that will trigger this warning: if numberOfLines is set to anything but 1, the warning will happen regardless of if you have preferredMaxLayoutWidth set or not.
...
Database Design for Tagging
...hilippkeller.com/2005/04/24/Tags-Database-schemas/
along with performance tests:
http://howto.philippkeller.com/2005/06/19/Tagsystems-performance-tests/
Note that the conclusions there are very specific to MySQL, which (at least in 2005 at the time that was written) had very poor full text indexi...