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What's the difference between a proc and a lambda in Ruby?
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An example:
p = Proc.new {|a, b| puts a**2+b**2 } # => #<Proc:0x3c7d28@(irb):1>
p.call 1, 2 # => 5
p.call 1 # => NoMethodError: undefined method `**' for nil:NilClass
p.call 1, 2, 3 # => 5
l = lambda {|a, b| puts a**2+b**2 } # => #<Proc:0x15016c@(irb):5 (lambda)>
l.ca...
“INSERT IGNORE” vs “INSERT … ON DUPLICATE KEY UPDATE”
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1003
I would recommend using INSERT...ON DUPLICATE KEY UPDATE.
If you use INSERT IGNORE, then the ro...
Resize image proportionally with MaxHeight and MaxWidth constraints
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3 Answers
3
Active
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How to format a floating number to fixed width in Python
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for x in numbers:
print "{:10.4f}".format(x)
prints
23.2300
0.1233
1.0000
4.2230
9887.2000
The format specifier inside the curly braces follows the Python format string syntax. Specifically, in this case, it consists of the following parts:
The empty string bef...
Select every Nth element in CSS
...;/h1>
<div>1</div> <div>2</div>
<div>3</div> <div>4</div>
<h2></h2>
<div>5</div> <div>6</div>
<div>7</div> <div>8</div>
<h2></h2>
<div>9</div> <...
Skipping Iterations in Python
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398
You are looking for continue.
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Django removing object from ManyToMany relationship
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3 Answers
3
Active
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Python set to list
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Your code does work (tested with cpython 2.4, 2.5, 2.6, 2.7, 3.1 and 3.2):
>>> a = set(["Blah", "Hello"])
>>> a = list(a) # You probably wrote a = list(a()) here or list = set() above
>>> a
['Blah', 'Hello']
Check that you didn't overwrite list by accident...
What exactly is Java EE?
... maintain. Spring was then a much better alternative to EJB2. But since EJB3 (Java EE 5), the EJB API was much improved based on lessons learnt from Spring. Since CDI (Java EE 6), there's not really a reason to look at again another framework like Spring to make the developers more easy as to develo...
Pythonic way to create a long multi-line string
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2313
Are you talking about multi-line strings? Easy, use triple quotes to start and end them.
s = ...