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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...
How do I replace NA values with zeros in an R dataframe?
...nt in @gsk3 answer. A simple example:
> m <- matrix(sample(c(NA, 1:10), 100, replace = TRUE), 10)
> d <- as.data.frame(m)
V1 V2 V3 V4 V5 V6 V7 V8 V9 V10
1 4 3 NA 3 7 6 6 10 6 5
2 9 8 9 5 10 NA 2 1 7 2
3 1 1 6 3 6 NA 1 4 1 6
4 NA 4 NA 7 10 2 NA 4 1...
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...
How to remove leading zeros from alphanumeric text?
...s leading zeroes, but leaves one if necessary (i.e. it wouldn't just turn "0" to a blank string).
s.replaceFirst("^0+(?!$)", "")
The ^ anchor will make sure that the 0+ being matched is at the beginning of the input. The (?!$) negative lookahead ensures that not the entire string will be matched....
Disable/turn off inherited CSS3 transitions
..." class="transition">Content</a>
...and CSS:
a {
color: #f90;
-webkit-transition:color 0.8s ease-in, background-color 0.1s ease-in ;
-moz-transition:color 0.8s ease-in, background-color 0.1s ease-in;
-o-transition:color 0.8s ease-in, background-color 0.1s ease-in;
...
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...
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'...
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
...
How to truncate the time on a DateTime object in Python?
...
390
I think this is what you're looking for...
>>> import datetime
>>> dt = datet...
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...