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String's Maximum length in Java - calling length() method
..., which is 2^31 - 1 (or approximately 2 billion.)
In terms of lengths and indexing of arrays, (such as char[], which is probably the way the internal data representation is implemented for Strings), Chapter 10: Arrays of The Java Language Specification, Java SE 7 Edition says the following:
The...
NSInvocation for Dummies?
... any arguments for that method:
[myInvocation setArgument:&myString atIndex:2];
Note that object arguments must be passed by pointer. Thank you to Ryan McCuaig for pointing that out, and please see Apple's documentation for more details.
At this point, myInvocation is a complete object, desc...
Static Indexers?
Why are static indexers disallowed in C#? I see no reason why they should not be allowed and furthermore they could be very useful.
...
What's the difference between process.cwd() vs __dirname?
...
$ find proj
proj
proj/src
proj/src/index.js
$ cat proj/src/index.js
console.log("process.cwd() = " + process.cwd());
console.log("__dirname = " + __dirname);
$ cd proj; node src/index.js
process.cwd() = /tmp/proj
__dirname = /tmp/proj/src
...
Get first key in a (possibly) associative array?
...
2019 Update
Starting from PHP 7.3, there is a new built in function called array_key_first() which will retrieve the first key from the given array without resetting the internal pointer. Check out the documentation for more info.
You can use reset and key:
reset($array);
$first_key = key(...
How to handle click event in Button Column in Datagridview?
...here and even provided by the documentation at MSDN to hardcode the column index or column name in order to determine if a button was clicked. The click event registers for the entire grid, so somehow you need to determine that a button was clicked, but you should not do so by assuming that your bu...
Having issue with multiple controllers of the same name in my project
...n}/{id}", // URL with parameters
new { controller = "Home", action = "Index", id = UrlParameter.Optional }, // Parameter defaults
new string[] { "MyCompany.MyProject.WebMvc.Controllers"}
);
This will make http://server/ go to your HomeController's Index action which is, I think, what you...
How to calculate moving average using NumPy?
...y be is faster than FFT based methods:
EDIT Corrected an off-by-one wrong indexing spotted by Bean in the code. EDIT
def moving_average(a, n=3) :
ret = np.cumsum(a, dtype=float)
ret[n:] = ret[n:] - ret[:-n]
return ret[n - 1:] / n
>>> a = np.arange(20)
>>> moving_aver...
ALTER TABLE to add a composite primary key
...
They both enforce uniqueness on that set of three fields, however from an indexing standpoint there is a difference. The fields are indexed from left to right.
For example, consider the following queries:
A) SELECT person, place, thing FROM provider WHERE person = 'foo' AND thing = 'bar';
B) SELE...
Saving timestamp in mysql table using php
...But when I pass the timestamp ( 1299762201428 ) to the record, it automatically saves the value 0000-00-00 00:00:00 into that table.
...