大约有 14,100 项符合查询结果(耗时:0.0349秒) [XML]
For each row in an R dataframe
... B P2 2 200
3 C P3 3 300
> f <- function(x, output) {
wellName <- x[1]
plateName <- x[2]
wellID <- 1
print(paste(wellID, x[3], x[4], sep=","))
cat(paste(wellID, x[3], x[4], sep=","), file= output, append = T, fill = T)
}
> apply(d, 1, f, output = '...
Get the client IP address using PHP [duplicate]
...))
$ipaddress = getenv('HTTP_CLIENT_IP');
else if(getenv('HTTP_X_FORWARDED_FOR'))
$ipaddress = getenv('HTTP_X_FORWARDED_FOR');
else if(getenv('HTTP_X_FORWARDED'))
$ipaddress = getenv('HTTP_X_FORWARDED');
else if(getenv('HTTP_FORWARDED_FOR'))
$ipaddress = g...
How to get a reference to current module's attributes in Python
...
A classic case of "I need X (to get Y done) -> You don't need X you need Z". I do need X though! No offense, I just find this amusing, and the most voted answer gives me the answer I need :)
– pawamoy
Sep 14 '...
Binary search (bisection) in Python
...
from bisect import bisect_left
def binary_search(a, x, lo=0, hi=None): # can't use a to specify default for hi
hi = hi if hi is not None else len(a) # hi defaults to len(a)
pos = bisect_left(a, x, lo, hi) # find insertion position
return pos if pos != hi and ...
Explain how finding cycle start node in cycle linked list work?
I understand that Tortoise and Hare's meeting concludes the existence of loop, but how does moving tortoise to beginning of linked list while keeping the hare at meeting place, followed by moving both one step at a time make them meet at starting point of cycle?
...
Adding two Java 8 streams, or an extra element to a stream
I can add streams or extra elements, like this:
8 Answers
8
...
Removing first x characters from string?
How might one remove the first x characters from a string? For example, if one had a string lipsum , how would they remove the first 3 characters and get a result of sum ?
...
Why does Go have a “goto” statement
... standard library, we can see where gotos are actually well applied.
For example, in the math/gamma.go file, the goto statement is used:
for x < 0 {
if x > -1e-09 {
goto small
}
z = z / x
x = x + 1
}
for x < 2 {
if x < 1e-09 {
goto small
}
...
Is it Pythonic to use list comprehensions for just side effects?
...t is created, and it could potentially be very, very large, and therefore expensive to create.
share
|
improve this answer
|
follow
|
...
Get the first element of each tuple in a list in Python [duplicate]
...
Use a list comprehension:
res_list = [x[0] for x in rows]
Below is a demonstration:
>>> rows = [(1, 2), (3, 4), (5, 6)]
>>> [x[0] for x in rows]
[1, 3, 5]
>>>
Alternately, you could use unpacking instead of x[0]:
res_list = [x f...