大约有 45,000 项符合查询结果（耗时：0.0442秒） [XML]
Is there an R function for finding the index of an element in a vector?
...rks on vectors :
x <- sample(1:10)
x
# [1] 4 5 9 3 8 1 6 10 7 2
match(c(4,8),x)
# [1] 1 5
match only returns the first encounter of a match, as you requested. It returns the position in the second argument of the values in the first argument.
For multiple matching, %in% is the way to...
Swift double to string
...
213
It is not casting, it is creating a string from a value with a format.
let a: Double = 1.5
let...
Python: Find in list
...
1235
As for your first question: that code is perfectly fine and should work if item equals one of ...
How can I make Flexbox children 100% height of their parent?
...
277
Use align-items: stretch
Similar to David Storey's answer, my workaround is:
.flex-2 {
d...
How to suppress Update Links warning?
...
UPDATE:
After all the details summarized and discussed, I spent 2 fair hours in checking the options, and this update is to dot all is.
Preparations
First of all, I performed a clean Office 2010 x86 install on Clean Win7 SP1 Ultimate x64 virtual machine powered by VMWare (this is usual ...
Exif manipulation library for python [closed]
...
12 Answers
12
Active
...
Appending an element to the end of a list in Scala
...
List(1,2,3) :+ 4
Results in List[Int] = List(1, 2, 3, 4)
Note that this operation has a complexity of O(n). If you need this operation frequently, or for long lists, consider using another data type (e.g. a ListBuffer).
...
Convert columns to string in Pandas
...n (and therefore your keys to strings):
In [11]: df = pd.DataFrame([['A', 2], ['A', 4], ['B', 6]])
In [12]: df.to_json()
Out[12]: '{"0":{"0":"A","1":"A","2":"B"},"1":{"0":2,"1":4,"2":6}}'
In [13]: df[0].to_json()
Out[13]: '{"0":"A","1":"A","2":"B"}'
Note: you can pass in a buffer/file to save t...
Changing the “tick frequency” on x or y axis in matplotlib?
...rt numpy as np
import matplotlib.pyplot as plt
x = [0,5,9,10,15]
y = [0,1,2,3,4]
plt.plot(x,y)
plt.xticks(np.arange(min(x), max(x)+1, 1.0))
plt.show()
(np.arange was used rather than Python's range function just in case min(x) and max(x) are floats instead of ints.)
The plt.plot (or ax.plot...
Is there an easy way to create ordinals in C#?
...
21 Answers
21
Active
...