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How are echo and print different in PHP? [duplicate]
...a difference between the two, but speed-wise it
should be irrelevant which one you use. echo is marginally faster
since it doesn't set a return value if you really want to get down to the
nitty gritty.
Expression. print() behaves like a function in that you can do:
$ret = print "Hello World"; A...
How do I assert equality on two classes without an equals method?
...atcher:
For latest version of Mockito use:
Assert.assertTrue(new ReflectionEquals(expected, excludeFields).matches(actual));
For older versions use:
Assert.assertThat(actual, new ReflectionEquals(expected, excludeFields));
...
Why are floating point numbers inaccurate?
...g point numbers are represented a lot like scientific notation: with an exponent and a mantissa (also called the significand). A very simple number, say 9.2, is actually this fraction:
5179139571476070 * 2 -49
Where the exponent is -49 and the mantissa is 5179139571476070. The reason it is imp...
Hidden Features of C++? [closed]
...
But only one per function, i suspect? :)
– Constantin
Oct 5 '08 at 17:40
51
...
Regex exactly n OR m times
...?? is lazy, ? is greedy)
*, *? - any number of occurences
+, +? - at least one occurence
{n} - exactly n occurences
{n,m} - n to m occurences, inclusive
{n,m}? - n to m occurences, lazy
{n,}, {n,}? - at least n occurence
To get "exactly N or M", you need to write the quantified regex twice, unless...
Difference between volatile and synchronized in Java
...ly, and the second to do with when the effects in memory of what has been done are visible to other threads. Because each CPU has several levels of cache between it and main memory, threads running on different CPUs or cores can see "memory" differently at any given moment in time because threads a...
How can I get list of values from dict?
...
There should be one ‒ and preferably only one ‒ obvious way to do it.
Therefore list(dictionary.values()) is the one way.
Yet, considering Python3, what is quicker?
[*L] vs. [].extend(L) vs. list(L)
small_ds = {x: str(x+42) for x in...
How would one write object-oriented code in C? [closed]
...t class, you just change the pointers to point to your own functions. Everyone that called those functions would do it through the function pointers, giving you your polymorphism:
int stat = (commTcp.open)(commTcp, "bigiron.box.com:5000");
Sort of like a manual vtable.
You could even have virtua...
Drop rows with all zeros in pandas data frame
... Just a note: OP wanted to drop rows with all columns having value 0, but one can infer all method.
– paulochf
Apr 25 '16 at 20:02
1
...
Loading and parsing a JSON file with multiple JSON objects
...ns JSON per line, you are saved the headaches of trying to parse it all in one go or to figure out a streaming JSON parser. You can now opt to process each line separately before moving on to the next, saving memory in the process. You probably don't want to append each result to one list and then p...