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How to generate random SHA1 hash to use as ID in node.js?
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edited May 23 '17 at 12:10
Community♦
111 silver badge
answered Feb 23 '12 at 6:28
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Static variables in member functions
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iammilindiammilind
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Change Active Menu Item on Page Scroll?
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207
It's done by binding to the scroll event of the container (usually window).
Quick example:
//...
How do I convert an integer to binary in JavaScript?
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function dec2bin(dec){
return (dec >>> 0).toString(2);
}
dec2bin(1); // 1
dec2bin(-1); // 11111111111111111111111111111111
dec2bin(256); // 100000000
dec2bin(-256); // 11111111111111111111111100000000
You can use Number.toString(2) function, but it has ...
Accessing class variables from a list comprehension in the class definition
...owing will fail:
class A:
a = 42
b = list(a + i for i in range(10))
So, to summarize: you cannot access the class scope from functions, list comprehensions or generator expressions enclosed in that scope; they act as if that scope does not exist. In Python 2, list comprehensions were i...
Nested JSON objects - do I have to use arrays for everything?
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204
You don't need to use arrays.
JSON values can be arrays, objects, or primitives (numbers or st...
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...
Which is better, number(x) or parseFloat(x)?
... same:
parseFloat('3'); // => 3
Number('3'); // => 3
parseFloat('1.501'); // => 1.501
Number('1.501'); // => 1.501
parseFloat('1e10'); // => 10000000000
Number('1e10'); // => 10000000000
So as long as you have standard numeric input, there's no difference. However, if your input...
Hadoop “Unable to load native-hadoop library for your platform” warning
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230
I assume you're running Hadoop on 64bit CentOS. The reason you saw that warning is the native Ha...
How to append rows to an R data frame
...sive insight than system.time:
library(microbenchmark)
microbenchmark(f1(1000), f3(1000), f4(1000), times = 5)
# Unit: milliseconds
# expr min lq median uq max neval
# f1(1000) 1024.539618 1029.693877 1045.972666 1055.25931 1112.769176 5
# f3(1000) ...