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How to avoid the “divide by zero” error in SQL?
... by zero" error we have programmed it like this:
Select Case when divisor=0 then null
Else dividend / divisor
End ,,,
But here is a much nicer way of doing it:
Select dividend / NULLIF(divisor, 0) ...
Now the only problem is to remember the NullIf bit, if I use the "/" key.
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How to make blinking/flashing text with CSS 3
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Can't connect to local MySQL server through socket '/tmp/mysql.sock
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PratyayPratyay
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Standard deviation of a list
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Since Python 3.4 / PEP450 there is a statistics module in the standard library, which has a method stdev for calculating the standard deviation of iterables like yours:
>>> A_rank = [0.8, 0.4, 1.2, 3.7, 2.6, 5.8]
>>> import statis...
.NET 4.0 has a new GAC, why?
...the new GAC . Does it mean now we have to manage two GACs, one for .NET 2.0-3.5 applications and the other for .NET 4.0 applications?
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Split a String into an array in Swift?
... like so:
var fullName = "First Last"
var fullNameArr = split(fullName) {$0 == " "}
var firstName: String = fullNameArr[0]
var lastName: String? = fullNameArr.count > 1 ? fullNameArr[1] : nil
with Swift 2
In Swift 2 the use of split becomes a bit more complicated due to the introduction of t...
Pandas get topmost n records within each group
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>>> df.groupby('id').head(2)
id value
id
1 0 1 1
1 1 2
2 3 2 1
4 2 2
3 7 3 1
4 8 4 1
(Keep in mind that you might need to order/sort before, depending on your data)
EDIT: As mentioned by the questioner, use df.gro...
Java: parse int value from a char
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edited Apr 30 '18 at 4:24
Neuron
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a...
In-memory size of a Python structure
...gt;>> import decimal
>>>
>>> d = {
... "int": 0,
... "float": 0.0,
... "dict": dict(),
... "set": set(),
... "tuple": tuple(),
... "list": list(),
... "str": "a",
... "unicode": u"a",
... "decimal": decimal.Decimal(0),
... "object": ob...
Can I add jars to maven 2 build classpath without installing them?
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Problems of popular approaches
Most of the answers you'll find around the internet will suggest...