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What's quicker and better to determine if an array key exists in PHP?
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isset() is faster, but it's not the same as array_key_exists().
array_key_exists() purely checks if the key exists, even if the value is NULL.
Whereas
isset() will return false if the key exist and value is NULL.
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Determine Whether Integer Is Between Two Other Integers?
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Paolo MorettiPaolo Moretti
45.4k2121 gold badges9191 silver badges8888 bronze badges
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how to calculate binary search complexity
... search hence it is log(n) algorithm. Since I am not from a mathematics background I am not able to relate to it. Can somebody explain it in a little more detail? does it have to do something with the logarithmic series?
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How do you attach and detach from Docker's process?
I can attach to a docker process but Ctrl + c doesn't work to detach from it. exit basically halts the process.
15 Ans...
How to replace NaN values by Zeroes in a column of a Pandas Dataframe?
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I believe DataFrame.fillna() will do this for you.
Link to Docs for a dataframe and for a Series.
Example:
In [7]: df
Out[7]:
0 1
0 NaN NaN
1 -0.494375 0.570994
2 NaN NaN
3 1.876360 -0.229738
4 NaN NaN
In [8]: df.fill...
How do I check if a number is a palindrome?
How do I check if a number is a palindrome?
50 Answers
50
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How to increase the Java stack size?
I asked this question to get to know how to increase the runtime call stack size in the JVM. I've got an answer to this, and I've also got many useful answers and comments relevant to how Java handles the situation where a large runtime stack is needed. I've extended my question with the summary of ...
The cast to value type 'Int32' failed because the materialized value is null
... executed as code, but rather translated into SQL. Sometimes this is a "leaky abstraction" that yields unexpected behaviour.
One such case is null handling, where there can be unexpected nulls in different places. ...DefaultIfEmpty(0).Sum(0) can help in this (quite simple) case, where there might ...
Samples of Scala and Java code where Scala code looks simpler/has fewer lines?
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Let's improve stacker's example and use Scala's case classes:
case class Person(firstName: String, lastName: String)
The above Scala class contains all features of the below Java class, and some more - for example it supports pattern matchi...
PHP Pass by reference in foreach [duplicate]
...e to the last array item, so it's overwritten each time.
You can see it like that:
$a = array ('zero','one','two', 'three');
foreach ($a as &$v) {
}
foreach ($a as $v) {
echo $v.'-'.$a[3].PHP_EOL;
}
As you can see, the last array item takes the current loop value: 'zero', 'one', 'two', ...