大约有 45,000 项符合查询结果（耗时：0.0688秒） [XML]
Index all *except* one item in python
... # [9, 8, 7, 6, 5, 4, 3, 2, 1, 0]
b = [x for i,x in enumerate(a) if i!=3] # [9, 8, 7, 5, 4, 3, 2, 1, 0]
This is very general, and can be used with all iterables, including numpy arrays. If you replace [] with (), b will be an iterator instead of a list.
Or you could do this in-place ...
Exception handling in R [closed]
...wordpress/?p=15.
for(i in 1:16){
result <- try(nonlinear_modeling(i));
if(class(result) == "try-error") next;
}
share
|
improve this answer
|
follow
|
...
echo that outputs to stderr
...
FYI: if you want to format or do anything besides simply echo the string then you'll have to move the redirect back to the end. For example errcho(){ >&2 echo $@|pr -To5;} won't work. To do something like that you'll have...
PHP, get file name without file extension
... is absolutely correct. pathinfo operates on strings, so it doesn't matter if the file is actually on the server or not.
– Gordon
Feb 2 '10 at 11:22
13
...
How do I read the first line of a file using cat?
...
There are many different ways:
sed -n 1p file
head -n 1 file
awk 'NR==1' file
share
|
improve this answer
|
follo...
Why is printing “B” dramatically slower than printing “#”?
...hose lessons stick with you, they get burned in to your lizard brain. But if you leaned to code after that, when your environment word wraps everything, or you do it manually prior to runtime, it is harder to run into the issues with word wrap.
– JockM
Feb 23 ...
Local and global temporary tables in SQL Server
What is the difference between local and global temporary tables in SQL Server?
7 Answers
...
Running multiple commands in one line in shell
...ou are looking for is && operator to execute the next command only if the previous one succeeded:
cp /templates/apple /templates/used && cp /templates/apple /templates/inuse && rm /templates/apple
Or
cp /templates/apple /templates/used && mv /templates/apple /tem...
Why are quaternions used for rotations?
...ndependent components--it's constrained. A two dimensional rotation is specified by three coordinates in three dimensions, regardless of representation. Matrices have more components in general because they can do more than rotations. But in the case of rotations the extra components are determined ...
How to continue a task when Fabric receives an error
When I define a task to run on several remote servers, if the task runs on server one and exits with an error, Fabric will stop and abort the task. But I want to make fabric ignore the error and run the task on the next server. How can I make it do this?
...