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How do I monitor the computer's CPU, memory, and disk usage in Java?
... = 390625000 is only how long that thread has been running. That is not really useful for determining the processor usage
– MikeNereson
Jul 14 '09 at 15:35
2
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invalid byte sequence for encoding “UTF8”
... the iconv utility to change encoding of the input data.
iconv -f original_charset -t utf-8 originalfile > newfile
You can change psql (the client) encoding following the instructions on Character Set Support. On that page, search for the phrase "To enable automatic character set conversion".
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Proper way to exit iPhone application?
... it to exit due to certain user actions. After cleaning up memory the app allocated, what's the appropriate method to call to terminate the application?
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How do you prevent IDisposable from spreading to all your classes?
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You can't really "prevent" IDisposable from spreading. Some classes need to be disposed, like AutoResetEvent, and the most efficient way is to do it in the Dispose() method to avoid the overhead of finalizers. But this method must be cal...
data.table vs dplyr: can one do something well the other can't or does poorly?
...j and by together is by design. By keeping related operations together, it allows to easily optimise operations for speed and more importantly memory usage, and also provide some powerful features, all while maintaining the consistency in syntax.
1. Speed
Quite a few benchmarks (though mostly on g...
HTML5 Canvas 100% Width Height of Viewport?
....getContext('2d');
// resize the canvas to fill browser window dynamically
window.addEventListener('resize', resizeCanvas, false);
function resizeCanvas() {
canvas.width = window.innerWidth;
canvas.height = window.innerHeight;
/**
* You...
What does the [Flags] Enum Attribute mean in C#?
... Such collections are often used with bitwise operators, for example:
var allowedColors = MyColor.Red | MyColor.Green | MyColor.Blue;
Note that the [Flags] attribute doesn't enable this by itself - all it does is allow a nice representation by the .ToString() method:
enum Suits { Spades = 1, Clu...
Summarizing multiple columns with dplyr? [duplicate]
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The dplyr package contains summarise_all for this aim:
library(dplyr)
df %>% group_by(grp) %>% summarise_all(list(mean))
#> # A tibble: 3 x 5
#> grp a b c d
#> <int> <dbl> <dbl> <dbl> <dbl>
#>...
void in C# generics?
...nctions need to return null, but if it unifies your code, it should be a small price to pay.
This inability to use void as a return type is at least partially responsible for a split between the Func<...> and Action<...> families of generic delegates: had it been possible to return void...
JSON Stringify changes time of date because of UTC
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thanks... I actually found a great library here, blog.stevenlevithan.com/archives/date-time-format all you need to do this (maybe it will help you) , you pass false and it doesn't convert. var something = dateFormat(myStartDate, "isoDateTi...