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What to use as an initial version? [closed]
I usually start my projects with a version 1.0.0. As soon as I have some stuff together, I release it as 1.0.0 and move on with 1.1.0.
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What does `kill -0 $pid` in a shell script do?
Basically, what signal does '0' represent, because here I see SIGNAL numbers starting from 1.
6 Answers
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Remove duplicated rows using dplyr
...r below:
library(dplyr)
set.seed(123)
df <- data.frame(
x = sample(0:1, 10, replace = T),
y = sample(0:1, 10, replace = T),
z = 1:10
)
One approach would be to group, and then only keep the first row:
df %>% group_by(x, y) %>% filter(row_number(z) == 1)
## Source: local data fr...
How to add a new row to an empty numpy array
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The way to "start" the array that you want is:
arr = np.empty((0,3), int)
Which is an empty array but it has the proper dimensionality.
>>> arr
array([], shape=(0, 3), dtype=int64)
Then be sure to append along axis 0:
arr = np.append(arr, np.array([[1,2,3]]), axis=0)
arr =...
Most efficient way to create a zero filled JavaScript array?
...duces Array.prototype.fill. It can be used like this:
new Array(len).fill(0);
Not sure if it's fast, but I like it because it's short and self-describing.
It's still not in IE (check compatibility), but there's a polyfill available.
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postgresql return 0 if returned value is null
...n
WHERE listing_Type = 'AARM'
AND u_kbalikepartnumbers_id = 1000307
AND ( EXTRACT( DAY FROM ( NOW() - dateEnded ) ) ) * 24 < 48
AND COALESCE( price, 0 ) > ( SELECT AVG( COALESCE( price, 0 ) )* 0.50
FROM ( SELECT *, cume_dist() ...
Implement Stack using Two Queues
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Richard
40.9k2222 gold badges134134 silver badges203203 bronze badges
answered Mar 27 '09 at 2:17
SvanteSvante...
Why does this assert throw a format exception when comparing structures?
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100
I've got it. And yes, it's a bug.
The problem is that there are two levels of string.Format go...
Validate that a string is a positive integer
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302
Two answers for you:
Based on parsing
Regular expression
Note that in both cases, I've inte...