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Finding sum of elements in Swift array

...d. Swift 3 and Swift 4: let multiples = [...] let sum = multiples.reduce(0, +) print("Sum of Array is : ", sum) Swift 2: let multiples = [...] sum = multiples.reduce(0, combine: +) Some more info: This uses Array's reduce method (documentation here), which allows you to "reduce a collectio...
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SQL keys, MUL vs PRI vs UNI

...at column. – pgoetz Aug 7 '19 at 16:07 add a comment  |  ...
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How do I convert a numpy array to (and display) an image?

... 240 You could use PIL to create (and display) an image: from PIL import Image import numpy as np w...
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Inline labels in Matplotlib

...e(np.int32) # mask stuff outside plot mask = (xy[:,0] >= 0) & (xy[:,0] < N) & (xy[:,1] >= 0) & (xy[:,1] < N) xy = xy[mask] # add to pop for p in xy: pop[l][tuple(p)] = 1.0 # find whitespace, nice place for label...
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CSS Box Shadow Bottom Only [duplicate]

... Do this: box-shadow: 0 4px 2px -2px gray; It's actually much simpler, whatever you set the blur to (3rd value), set the spread (4th value) to the negative of it. share ...
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Black transparent overlay on image hover with only CSS?

... the img element itself, see. .image { position: relative; width: 400px; height: 400px; } Give the child img element a width of 100% of the parent and add vertical-align:top to fix the default baseline alignment issues. .image img { width: 100%; vertical-align: top; } As for th...
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How to change navbar collapse threshold using Twitter bootstrap-responsive?

I'm using Twitter Bootstrap 2.0.1 in a Rails 3.1.2 project, implemented with bootstrap-sass. I'm loading both the bootstrap.css and the bootstrap-responsive.css files, as well as the bootstrap-collapse.js Javascript. ...
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Why does the order of the loops affect performance when iterating over a 2D array?

... 605 As others have said, the issue is the store to the memory location in the array: x[i][j]. Here'...
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How to find all combinations of coins when given some dollar value

...r any other convenient computer algebra system) to compute the answer for 10^10^6 dollars in a couple seconds in three lines of code. (And this was long enough ago that that’s a couple of seconds on a 75Mhz Pentium...) sh...
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Permutations in JavaScript?

... 108 If you notice, the code actually splits the chars into an array prior to do any permutation, so...