大约有 46,000 项符合查询结果（耗时：0.0356秒） [XML]
Difference between DateTime and Time in Ruby
What's the difference between DateTime and Time classes in Ruby and what factors would cause me to choose one or the other?
...
Getting the array length of a 2D array in Java
I need to get the length of a 2D array for both the row and column. I’ve successfully done this, using the following code:
...
Do you use NULL or 0 (zero) for pointers in C++?
...
Here's Stroustrup's take on this: C++ Style and Technique FAQ
In C++, the definition of NULL is 0, so there is only an aesthetic difference. I prefer to avoid macros, so I use 0. Another problem with NULL is that people sometimes mistakenly believe that it is differen...
What are Vertex Array Objects?
...://openglbook.com/the-book/
I got to chapter 2, where I draw a triangle, and I understand everything except VAOs (is this acronym OK?). The tutorial has this code:
...
Replace all 0 values to NA
...ays in ?'NULL',
NULL represents the null object in R
which is unique and, I guess, can be seen as the most uninformative and empty object.1 Then it becomes not so surprising that
data.frame(x = c(1, NULL, 2))
# x
# 1 1
# 2 2
That is, R does not reserve any space for this null object.2 Mea...
Can PNG image transparency be preserved when using PHP's GDlib imagecopyresampled?
...not the source image.
Edit:
full replacement code. See also answers below and their comments. This is not guaranteed to be be perfect in any way, but did achieve my needs at the time.
$uploadTempFile = $myField[ 'tmp_name' ]
list( $uploadWidth, $uploadHeight, $uploadType )
= getimagesize( $uplo...
List of lists changes reflected across sublists unexpectedly
...(3)]
which will reevaluate [1]*4 each time instead of evaluating it once and making 3 references to 1 list.
You might wonder why * can't make independent objects the way the list comprehension does. That's because the multiplication operator * operates on objects, without seeing expressions. Wh...
Shell equality operators (=, ==, -eq)
Can someone please explain the difference between = , == and -eq in shell scripting?
4 Answers
...
How to iterate through two lists in parallel?
I have two iterables in Python, and I want to go over them in pairs:
8 Answers
8
...
Formatting floats without trailing zeros
...t formatting rather than scientific notation, etc etc. Yeah, not as slick and elegant as %g, but, it works (and I don't know how to force %g to never use scientific notation;-).
share
|
improve thi...