大约有 18,000 项符合查询结果（耗时：0.0252秒） [XML]
Omit rows containing specific column of NA
I want to know how to omit NA values in a data frame, but only in some columns I am interested in.
8 Answers
...
Chrome, Javascript, window.open in new tab
In chrome this opens in a new tab:
8 Answers
8
...
Piping command output to tee but also save exit code of command [duplicate]
I have a shell script in which I wrap a command (mvn clean install), to redirect the output to a logfile.
4 Answers
...
Confused about stdin, stdout and stderr?
I am rather confused with the purpose of these three files. If my understanding is correct, stdin is the file in which a program writes into its requests to run a task in the process, stdout is the file into which the kernel writes its output and the process requesting it accesses the informatio...
Difference between ProcessBuilder and Runtime.exec()
I'm trying to execute an external command from java code, but there's a difference I've noticed between Runtime.getRuntime().exec(...) and new ProcessBuilder(...).start() .
...
NPM modules won't install globally without sudo
I have just reinstalled Ubuntu 12.04 LTS, and before anything else i did these steps :
14 Answers
...
Understanding dispatch_async
I have question around this code
3 Answers
3
...
Practical uses of different data structures [closed]
There's a lot of talk about data structures, but I can't find a simple list of data structures and their practical use out there. I'm trying to study for an interview and I think this would help me out, along with many others. I'm looking for something like this:
...
Find all storage devices attached to a Linux machine [closed]
I have a need to find all of the writable storage devices attached to a given machine, whether or not they are mounted.
7...
How to check if an object is a certain type
I am passing various objects to a subroutine to run the same process but using a different object each time. For example, in one case I am using a ListView and in another case I am passing a DropDownList.
...