大约有 18,000 项符合查询结果（耗时：0.0338秒） [XML]
How to count objects in PowerShell?
As I'm reading in the PowerShell user guide, one of the core PowerShell concepts is that commands accept and return objects instead of text. So for example, running get-alias returns me a number of System.Management.Automation.AliasInfo objects:
...
C++ SFINAE examples?
I want to get into more template meta-programming. I know that SFINAE stands for "substitution failure is not an error." But can someone show me a good use for SFINAE?
...
How can I check the syntax of Python script without executing it?
I used to use perl -c programfile to check the syntax of a Perl program and then exit without executing it. Is there an equivalent way to do this for a Python script?
...
How to log source file name and line number in Python
Is it possible to decorate/extend the python standard logging system, so that when a logging method is invoked it also logs the file and the line number where it was invoked or maybe the method that invoked it?
...
Detect if a NumPy array contains at least one non-numeric value?
... which will detect if the input contains at least one value which is non-numeric. If a non-numeric value is found I will raise an error (because the calculation should only return a numeric value). The number of dimensions of the input array is not known in advance - the function should give the cor...
Why is the minimalist, example Haskell quicksort not a “true” quicksort?
...quicksort has two beautiful aspects:
Divide and conquer: break the problem into two smaller problems.
Partition the elements in-place.
The short Haskell example demonstrates (1), but not (2). How (2) is done may not be obvious if you don't already know the technique!
...
How do I insert datetime value into a SQLite database?
I am trying to insert a datetime value into a SQLite database. It seems to be sucsessful but when I try to retrieve the value there is an error:
...
How do I provide custom cast support for my class?
How do I provide support for casting my class to other types? For example, if I have my own implementation of managing a byte[] , and I want to let people cast my class to a byte[] , which will just return the private member, how would I do this?
...
Remove rows with all or some NAs (missing values) in data.frame
I'd like to remove the lines in this data frame that:
16 Answers
16
...
Resync git repo with new .gitignore file
...
The solution mentioned in ".gitignore file not ignoring" is a bit extreme, but should work:
# rm all files
git rm -r --cached .
# add all files as per new .gitignore
git add .
# now, commit for new .gitignore to apply
git commit -m ".giti...