大约有 16,000 项符合查询结果（耗时：0.0378秒） [XML]
Combine two or more columns in a dataframe into a new column with a new name
...
Use paste.
df$x <- paste(df$n,df$s)
df
# n s b x
# 1 2 aa TRUE 2 aa
# 2 3 bb FALSE 3 bb
# 3 5 cc TRUE 5 cc
share
|
improve this answer
|
f...
“rm -rf” equivalent for Windows?
...
RMDIR or RD if you are using the classic Command Prompt (cmd.exe):
rd /s /q "path"
RMDIR [/S] [/Q] [drive:]path
RD [/S] [/Q] [drive:]path
/S Removes all directories and files in the specified directory in addition to the directory itsel...
assign multiple variables to the same value in Javascript
I have initialized several variables in the global scope in a JavaScript file:
5 Answers
...
Call a function from another file?
...te from file import function, and then call the function using function(a, b). The reason why this may not work, is because file is one of Python's core modules, so I suggest you change the name of your file.
Note that if you're trying to import functions from a.py to a file called b.py, you will n...
Android微信智能心跳方案 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...心跳就可以很大程度的保证下一次心跳环境是正常的。
b）成功一次认定，失败连续累积认定：成功是绝对的，连续失败多次才可能是失败。
c）临界值避免：我们使用比计算出的心跳稍微小一点的值做为稳定心跳避免临界值。...
Number of days in particular month of particular year?
...
Java 8 and later
@Warren M. Nocos.
If you are trying to use Java 8's new Date and Time API, you can use java.time.YearMonth class. See Oracle Tutorial.
// Get the number of days in that month
YearMonth yearMonthObject = YearMonth.of(1999, 2);
int daysInMonth = yearMonthObjec...
Assign pandas dataframe column dtypes
... I've had to manually parse into a list of lists, as the file was not amenable for pd.read_csv )
6 Answers
...
Creating a “logical exclusive or” operator in Java
...
Java does have a logical XOR operator, it is ^ (as in a ^ b).
Apart from that, you can't define new operators in Java.
Edit: Here's an example:
public static void main(String[] args) {
boolean[] all = { false, true };
for (boolean a : all) {
for (boolean b: all) ...
O(nlogn) Algorithm - Find three evenly spaced ones within binary string
...thms test yesterday, and I can't figure out the answer. It is driving me absolutely crazy, because it was worth about 40 points. I figure that most of the class didn't solve it correctly, because I haven't come up with a solution in the past 24 hours.
...
How to count the frequency of the elements in an unordered list?
...
Note: You should sort the list before using groupby.
You can use groupby from itertools package if the list is an ordered list.
a = [1,1,1,1,2,2,2,2,3,3,4,5,5]
from itertools import groupby
[len(list(group)) for key, group in groupby(a)]
Output:
[4, 4...