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What are type lambdas in Scala and what are their benefits?
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148
Type lambdas are vital quite a bit of the time when you are working with higher-kinded types.
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What does the star operator mean, in a function call?
...arguments, so you can do this:
def sum(a, b):
return a + b
values = (1, 2)
s = sum(*values)
This will unpack the tuple so that it actually executes as:
s = sum(1, 2)
The double star ** does the same, only using a dictionary and thus named arguments:
values = { 'a': 1, 'b': 2 }
s = sum(*...
warning: [options] bootstrap class path not set in conjunction with -source 1.5
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102
From a blog post:
To use javac from JDK N to cross-compiler to an older platform version, ...
How do I compute derivative using Numpy?
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143
You have four options
Finite Differences
Automatic Derivatives
Symbolic Differentiation
Com...
conditional unique constraint
... constraint like this. The difference is, you'll return false if Status = 1 and Count > 0.
http://msdn.microsoft.com/en-us/library/ms188258.aspx
CREATE TABLE CheckConstraint
(
Id TINYINT,
Name VARCHAR(50),
RecordStatus TINYINT
)
GO
CREATE FUNCTION CheckActiveCount(
@Id INT
) RETURNS I...
How do I list all cron jobs for all users?
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1149
You would have to run this as root, but:
for user in $(cut -f1 -d: /etc/passwd); do crontab ...
How do you change the size of figures drawn with matplotlib?
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17 Answers
17
Active
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How to express infinity in Ruby?
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188
If you use ruby 1.9.2, you can use:
>> Float::INFINITY #=> Infinity
>> 3 < ...