大约有 48,000 项符合查询结果（耗时：0.0651秒） [XML]
Validate that a string is a positive integer
...tive integer" to include 0, even though 0 is not positive. I include notes if you want to disallow 0.
Based on Parsing
If you want it to be a normalized decimal integer string over a reasonable range of values, you can do this:
function isNormalInteger(str) {
var n = Math.floor(Number(str));
...
Test for non-zero length string in Bash: [ -n “$var” ] or [ “$var” ]
I've seen Bash scripts test for a non-zero length string in two different ways. Most scripts use the -n option:
6 Answers...
Bash if [ false ] ; returns true
...command always succeeds. To actually run the command, drop the [ command.
if false; then
echo "True"
else
echo "False"
fi
share
|
improve this answer
|
follow
...
How do you test to see if a double is equal to NaN?
I have a double in Java and I want to check if it is NaN .
What is the best way to do this?
7 Answers
...
Use HTML5 to resize an image before upload
I have found a few different posts and even questions on stackoverflow answering this question. I am basically implementing this same thing as this post .
...
What function is to replace a substring from a string in C?
...'s algorithm for why strcpy can be annoying.)
// You must free the result if result is non-NULL.
char *str_replace(char *orig, char *rep, char *with) {
char *result; // the return string
char *ins; // the next insert point
char *tmp; // varies
int len_rep; // length of rep (t...
What is the Python equivalent of static variables inside a function?
...foo.counter += 1
print "Counter is %d" % foo.counter
foo.counter = 0
If you want the counter initialization code at the top instead of the bottom, you can create a decorator:
def static_vars(**kwargs):
def decorate(func):
for k in kwargs:
setattr(func, k, kwargs[k])
...
Batch file to delete files older than N days
...
For more goodies, refer to An A-Z Index of the Windows XP command line.
If you don't have forfiles installed on your machine, copy it from any Windows Server 2003 to your Windows XP machine at %WinDir%\system32\. This is possible since the EXE is fully compatible between Windows Server 2003 ...
Should I use multiplication or division?
...5 end'
real 0m7.997s
user 0m7.516s
sys 0m0.036s
=> no real difference
LuaJIT:
time luajit -O -e 'for i=1,1e8 do t=12341234234.234 / 2.0 end'
real 0m1.921s
user 0m1.668s
sys 0m0.004s
time luajit -O -e 'for i=1,1e8 do t=12341234234.234 * 0.5 end'
real 0m1.843s
user 0m...
What happens when a duplicate key is put into a HashMap?
If I pass the same key multiple times to HashMap ’s put method, what happens to the original value? And what if even the value repeats? I didn’t find any documentation on this.
...