大约有 37,000 项符合查询结果（耗时：0.0435秒） [XML]
Creating temporary files in bash
...voke mktemp something like
mydir=$(mktemp -d "${TMPDIR:-/tmp/}$(basename $0).XXXXXXXXXXXX")
which creates a temporary directory I can work in, and in which I can safely name the actual files something readable and useful.
mktemp is not standard, but it does exist on many platforms. The "X"s will...
Calculating sum of repeated elements in AngularJS ng-repeat
...</td>
In Controller
$scope.getTotal = function(){
var total = 0;
for(var i = 0; i < $scope.cart.products.length; i++){
var product = $scope.cart.products[i];
total += (product.price * product.quantity);
}
return total;
}
...
In Scala, what exactly does 'val a: A = _' (underscore) mean?
...he variable to a default value. From the Scala Language Specification:
0 if T is Int or one of its subrange types,
0L if T is Long,
0.0f if T is Float,
0.0d if T is Double,
false if T is Boolean,
() if T is Unit,
null for all other types T.
...
promise already under evaluation: recursive default argument reference or earlier problems?
...g the two instances where they occur we get:
f <- function(x, T) {
10 * sin(0.3 * x) * sin(1.3 * x^2) + 0.001 * x^3 + 0.2 * x + 80
}
g <- function(x, T, f. = f) { ## 1. note f.
exp(-f.(x)/T)
}
test<- function(g. = g, T = 1) { ## 2. note g.
g.(1,T)
}
test()
## [1] 8.560335e...
Convert JS date time to MySQL datetime
...nction to pad numbers to two digits…
**/
function twoDigits(d) {
if(0 <= d && d < 10) return "0" + d.toString();
if(-10 < d && d < 0) return "-0" + (-1*d).toString();
return d.toString();
}
/**
* …and then create the method to output the date string as ...
How to print a string in fixed width?
...
EDIT 2013-12-11 - This answer is very old. It is still valid and correct, but people looking at this should prefer the new format syntax.
You can use string formatting like this:
>>> print '%5s' % 'aa'
aa
>>>...
Is there an expression for an infinite generator?
...gument iter = zero-argument callable + sentinel value
int() always returns 0
Therefore, iter(int, 1) is an infinite iterator. There are obviously a huge number of variations on this particular theme (especially once you add lambda into the mix). One variant of particular note is iter(f, object()),...
How to get overall CPU usage (e.g. 57%) on Linux [closed]
...ke a look at cat /proc/stat
grep 'cpu ' /proc/stat | awk '{usage=($2+$4)*100/($2+$4+$5)} END {print usage "%"}'
EDIT please read comments before copy-paste this or using this for any serious work. This was not tested nor used, it's an idea for people who do not want to install a utility or for so...
When to use “new” and when not to, in C++? [duplicate]
...s out of scope. Some examples of this are:
void foo()
{
Point p = Point(0,0);
} // p is now destroyed.
for (...)
{
Point p = Point(0,0);
} // p is destroyed after each loop
Some people will say that the use of new decides whether your object is on the heap or the stack, but that is only true...
Prepend a level to a pandas MultiIndex
...
cs95
231k6060 gold badges392392 silver badges456456 bronze badges
answered Feb 7 '17 at 16:11
okartalokartal
...