大约有 44,000 项符合查询结果（耗时：0.0611秒） [XML]
Need a simple explanation of the inject method
I'm looking at this code but my brain is not registering how the number 10 can become the result. Would someone mind explaining what's happening here?
...
Unique (non-repeating) random numbers in O(1)?
I'd like to generate unique random numbers between 0 and 1000 that never repeat (i.e. 6 doesn't show up twice), but that doesn't resort to something like an O(N) search of previous values to do it. Is this possible?
...
Print second last column/field in awk
...
awk '{print $(NF-1)}'
Should work
share
|
improve this answer
|
follow
|
...
Python assigning multiple variables to same value? list behavior
... and Chris Wallace have a hot dog. If you change the first element of a to 1, the first elements of b and c are 1.
If you want to know if two names are naming the same object, use the is operator:
>>> a=b=c=[0,3,5]
>>> a is b
True
You then ask:
what is different from this...
How to scale down a range of numbers with a known min and max value
...anel. I want the height and width of each ellipse to be in a range of say 1-30. I have methods that find the minimum and maximum values from my data set, but I won't have the min and max until runtime. Is there an easy way to do this?
...
Aggregate / summarize multiple variables per group (e.g. sum, mean)
...he reshape2 package for this task:
require(reshape2)
df_melt <- melt(df1, id = c("date", "year", "month"))
dcast(df_melt, year + month ~ variable, sum)
# year month x1 x2
1 2000 1 -80.83405 -224.9540159
2 2000 2 -223.76331 -288.2418017
3 2000 3 -188.83930 -481....
What is the smallest possible valid PDF?
...
198
This is an interesting problem. Taking it by the book, you can start off with this:
%PDF-1.0...
Extract every nth element of a vector
...
163
a <- 1:120
b <- a[seq(1, length(a), 6)]
...
Get index of array element faster than O(n)
...
118
Convert the array into a hash. Then look for the key.
array = ['a', 'b', 'c']
hash = Hash[arr...