大约有 40,000 项符合查询结果（耗时：0.0575秒） [XML]
differentiate null=True, blank=True in django
When we add a database field in django we generally write:
18 Answers
18
...
Javascript shorthand ternary operator
...
Isn't it more correct to say if a is truthy vs. if a is evaluated to true?
– JaredPar
Jan 16 '12 at 17:54
3
...
How to get rid of blank pages in PDF exported from SSRS
...gs don't always work correctly under report properties. Have you tried manually dragging the report width in Visual Studio? That resolved this issue for me today after banging my head against the wall for a good while. Would be worth checking your header / footer widths also, they might be slightly ...
RuntimeError on windows trying python multiprocessing
...void creating subprocesses recursively.
Modified testMain.py:
import parallelTestModule
if __name__ == '__main__':
extractor = parallelTestModule.ParallelExtractor()
extractor.runInParallel(numProcesses=2, numThreads=4)
...
Why are all fields in an interface implicitly static and final?
I am just trying to understand why all fields defined in an Interface are implicitly static and final . The idea of keeping fields static makes sense to me as you can't have objects of an interface but why they are final (implicitly)?
...
Selecting only numeric columns from a data frame
...s.numeric)] works as well. And they always return data.frame. Compare x[1] vs x[,1] - first is data.frame, second is a vector. If one want to prevent conversion then must use x[, 1, drop=FALSE] .
– Marek
May 3 '11 at 11:46
...
What is the difference between cout, cerr, clog of iostream header in c++? When to use which one?
...e of them (e.g. program.exe >out.txt) would not affect the other.
Generally, stdout should be used for actual program output, while all information and error messages should be printed to stderr, so that if the user redirects output to a file, information messages are still printed on the screen...
Multiple variables in a 'with' statement?
...textlib.nested, this guarantees that a and b will have their __exit__()'s called even if C() or it's __enter__() method raises an exception.
You can also use earlier variables in later definitions (h/t Ahmad below):
with A() as a, B(a) as b, C(a, b) as c:
doSomething(a, c)
...
hasNext in Python iterators?
...thod to put the first element back after I have checked that it exists by calling next().
– Giorgio
Dec 24 '12 at 20:26
16
...
What is the best way to call a script from another script?
...s, methods, etc. I have another script which runs as a service. I want to call test1.py from the script running as a service.
...