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How do I replace NA values with zeros in an R dataframe?
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See my comment 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 ...
Python “extend” for a dictionary
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phoenix
3,20611 gold badge2727 silver badges3131 bronze badges
answered Feb 23 '09 at 11:01
Nick FortescueNic...
Access lapply index names inside FUN
...uments to the function, so the following works:
x <- list(a=11,b=12,c=13) # Changed to list to address concerns in commments
lapply(seq_along(x), function(y, n, i) { paste(n[[i]], y[[i]]) }, y=x, n=names(x))
Here I use lapply over the indices of x, but also pass in x and the names of x. As you...
What are the aspect ratios for all Android phone and tablet devices?
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║ 5 x 3 ║ 0.6 ║ 1.667... ║
╠══════════════════════════╬════════════════════════...
String formatting in Python 3
...at(self) # '<__main__.Player instance at 0x00BF7260>'
"games: {:>3}".format(player1.games) # 'games: 123'
"games: {:>3}".format(player2.games) # 'games: 4'
"games: {:0>3}".format(player2.games) # 'games: 004'
Note: As others pointed out, the new format does not supersede the ...
python pandas remove duplicate columns
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edited Aug 23 '19 at 13:30
Jean-François Corbett
33.6k2525 gold badges124124 silver badges172172 bronze badges
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Weighted random numbers
...andom number that is 0 or greater and is less than the sum of the weights
3) go through the items one at a time, subtracting their weight from your random number, until you get the item where the random number is less than that item's weight
Pseudo-code illustrating this:
int sum_of_weight = 0;
f...
What is sys.maxint in Python 3?
...a maximum integer, and I've read to use "sys.maxint" . However, in Python 3 when I call it I get:
6 Answers
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How to “properly” print a list?
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In Python 2:
mylist = ['x', 3, 'b']
print '[%s]' % ', '.join(map(str, mylist))
In Python 3 (where print is a builtin function and not a syntax feature anymore):
mylist = ['x', 3, 'b']
print('[%s]' % ', '.join(map(str, mylist)))
Both return:
[x, 3,...
Split list into smaller lists (split in half)
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238
A = [1,2,3,4,5,6]
B = A[:len(A)//2]
C = A[len(A)//2:]
If you want a function:
def split_list...