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How to scale SVG image to fill browser window?
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edited Jul 8 '12 at 3:26
answered Apr 13 '11 at 4:33
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Add unique constraint to combination of two columns
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223
Once you have removed your duplicate(s):
ALTER TABLE dbo.yourtablename
ADD CONSTRAINT uq_your...
Remove all the elements that occur in one list from another
...e following statement does exactly what you want and stores the result in l3:
l3 = [x for x in l1 if x not in l2]
l3 will contain [1, 6].
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Why is a pure virtual function initialized by 0?
...This is described in his book, The Design & Evolution of C++, section 13.2.3:
The curious =0 syntax was chosen ...
because at the time I saw no chance of
getting a new keyword accepted.
He also states explicitly that this need not set the vtable entry to NULL, and that doing so is not ...
Wrapping null-returning method in Java with Option in Scala?
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183
The Option companion object's apply method serves as a conversion function from nullable referen...
Algorithm to return all combinations of k elements from n
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Converting RGB to grayscale/intensity
...gt; L*
In color science, the common RGB values, as in html rgb( 10%, 20%, 30% ),
are called "nonlinear" or
Gamma corrected.
"Linear" values are defined as
Rlin = R^gamma, Glin = G^gamma, Blin = B^gamma
where gamma is 2.2 for many PCs.
The usual R G B are sometimes written as R' G' B' (R' = Rli...
Count number of matches of a regex in Javascript
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/*
* Example
*/
const count = (str) => {
const re = /[a-z]{3}/g
return ((str || '').match(re) || []).length
}
const str1 = 'abc, def, ghi'
const str2 = 'ABC, DEF, GHI'
console.log(`'${str1}' has ${count(str1)} occurrences of pattern '/[a-z]{3}/g'`)
console.log(`'${str2}' ...
In-memory size of a Python structure
Is there a reference for the memory size of Python data stucture on 32- and 64-bit platforms?
7 Answers
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Replace values in list using Python [duplicate]
...n-place if you want, but it doesn't actually save time:
items = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
for index, item in enumerate(items):
if not (item % 2):
items[index] = None
Here are (Python 3.6.3) timings demonstrating the non-timesave:
In [1]: %%timeit
...: items = [0, 1, 2, 3,...