大约有 44,300 项符合查询结果（耗时：0.0380秒） [XML]
Convert a String In C++ To Upper Case
...
29 Answers
29
Active
...
Properties vs Methods
...
152
From the Choosing Between Properties and Methods section of Design Guidelines for Developing Cla...
Repeat each row of data.frame the number of times specified in a column
...
Here's one solution:
df.expanded <- df[rep(row.names(df), df$freq), 1:2]
Result:
var1 var2
1 a d
2 b e
2.1 b e
3 c f
3.1 c f
3.2 c f
share
|
im...
Getting and removing the first character of a string
I would like to do some 2-dimensional walks using strings of characters by assigning different values to each character. I was planning to 'pop' the first character of a string, use it, and repeat for the rest of the string.
...
How to view UTF-8 Characters in VIM or Gvim
...
62
Try to reload the document using:
:e! ++enc=utf8
If that works you should maybe change the f...
Working with huge files in VIM
I tried opening a huge (~2GB) file in VIM but it choked. I don't actually need to edit the file, just jump around efficiently.
...
Why would a post-build step (xcopy) occasionally exit with code 2 in a TeamCity build?
...ying is a file or a directory. This error will appear as "exited with code 2". When you run the same xcopy at a command prompt, you'll see that xcopy is asking for a response of file or directory.
To resolve this issue with an automated build, you can echo in a pre-defined response with a pipe.
To...
Function Pointers in Java
...
126
The Java idiom for function-pointer-like functionality is an an anonymous class implementing an...
List comprehension vs map
...n map needs a lambda:
$ python -mtimeit -s'xs=range(10)' 'map(lambda x: x+2, xs)'
100000 loops, best of 3: 4.24 usec per loop
$ python -mtimeit -s'xs=range(10)' '[x+2 for x in xs]'
100000 loops, best of 3: 2.32 usec per loop
...