大约有 47,000 项符合查询结果（耗时：0.0642秒） [XML]
Why is SSE scalar sqrt(x) slower than rsqrt(x) * x?
I've been profiling some of our core math on an Intel Core Duo, and while looking at various approaches to square root I've noticed something odd: using the SSE scalar operations, it is faster to take a reciprocal square root and multiply it to get the sqrt, than it is to use the native sqrt opcode!...
How does PHP 'foreach' actually work?
Let me prefix this by saying that I know what foreach is, does and how to use it. This question concerns how it works under the bonnet, and I don't want any answers along the lines of "this is how you loop an array with foreach ".
...
Is False == 0 and True == 1 an implementation detail or is it guaranteed by the language?
Is it guaranteed that False == 0 and True == 1 , in Python (assuming that they are not reassigned by the user)? For instance, is it in any way guaranteed that the following code will always produce the same results, whatever the version of Python (both existing and, likely, future ones)?
...
Getting the closest string match
I need a way to compare multiple strings to a test string and return the string that closely resembles it:
12 Answers
...
How does tuple comparison work in Python?
I have been reading the Core Python programming book, and the author shows an example like:
4 Answers
...
Why doesn't Python have a sign function?
I can't understand why Python doesn't have a sign function. It has an abs builtin (which I consider sign 's sister), but no sign .
...
Is there a difference between x++ and ++x in java?
Is there a difference between ++x and x++ in java?
16 Answers
16
...
Why does 1==1==1 return true, “1”==“1”==“1” return true, and “a...
I tested the above code in Chrome's console and for some reason, a() returns true, b() returns true, and c() returns false.
...
Pointers in Python?
...
I want form.data['field'] and
form.field.value to always have the
same value
This is feasible, because it involves decorated names and indexing -- i.e., completely different constructs from the barenames a and b that you're asking about, and for...
Sleep until a specific time/date
I want my bash script to sleep until a specific time. So, I want a command like "sleep" which takes no interval but an end time and sleeps until then.
...