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select count(*) from table of mysql in php
... to alias the aggregate using the as keyword in order to call it from mysql_fetch_assoc
$result=mysql_query("SELECT count(*) as total from Students");
$data=mysql_fetch_assoc($result);
echo $data['total'];
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Why is lazy evaluation useful?
...epending on the sequence of conditional expressions, only a subset may actually be used. In a language like C, all three values would be computed anyway; but in Haskell, only the necessary values are computed.
It also allows for cool stuff like infinite lists. I can't have an infinite list in a lan...
Hidden features of Scala
... more. Every Regex object in Scala has an extractor (see answer from oxbox_lakes above) that gives you access to the match groups. So you can do something like:
// Regex to split a date in the format Y/M/D.
val regex = "(\\d+)/(\\d+)/(\\d+)".r
val regex(year, month, day) = "2010/1/13"
The secon...
How to pass a user defined argument in scrapy spider
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The above code is only partially working for me. For eg. If I define domain using self.domain, I'm still not able to access it outside the __init__ method. Python throws a not defined error. BTW, why have you omitted the super call? PS. I'm working wit...
How do I design a class in Python?
I've had some really awesome help on my previous questions for detecting paws and toes within a paw , but all these solutions only work for one measurement at a time.
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How dangerous is it to compare floating point values?
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First of all, floating point values are not "random" in their behavior. Exact comparison can and does make sense in plenty of real-world usages. But if you're going to use floating point you need to be aware of how it works. Erring on...
How to add an extra column to a NumPy array
...for a way to add a bias unit to my artificial neuronal network in batch on all layers at once, and this is the perfect answer.
– gaborous
Aug 18 '16 at 15:07
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Perform commands over ssh with Python
...to automate some command line commands in Python. At the moment I'm doing calls thus:
13 Answers
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What does the variable $this mean in PHP?
I see the variable $this in PHP all the time and I have no idea what it's used for. I've never personally used it.
10 An...
Why does C++ require a user-provided default constructor to default-construct a const object?
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This was considered a defect (against all versions of the standard) and it was resolved by Core Working Group (CWG) Defect 253. The new wording for the standard states in http://eel.is/c++draft/dcl.init#7
A class type T is const-default-constructible if
def...