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Defining an array of anonymous objects in CoffeeScript
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island205island205
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Java HashMap performance optimization / alternative
...et = very very bad. However if I turn the two arrays into a number in base 52 I am guaranteed to get a unique hash code for every object:
public int hashCode() {
// assume that both a and b are sorted
return a[0] + powerOf52(a[1], 1) + powerOf52(b[0], 2) + powerOf52(b[1], 3) +...
How many double numbers are there between 0.0 and 1.0?
...
Java doubles are in IEEE-754 format, therefore they have a 52-bit fraction; between any two adjacent powers of two (inclusive of one and exclusive of the next one), there will therefore be 2 to the 52th power different doubles (i.e., 4503599627370496 of them). For example, that's th...
vs2010编译boost若干问题解决 - 开源 & Github - 清泛网 - 专注C/C++及内核技术
...ttp: www.boost.org users download 上下载boost安装包，我下的是1.52.0版。按照说明，直接运行bootstr...首先说下环境，win7，vs2010。
先在http://www.boost.org/users/download/上下载boost安装包，我下的是1.52.0版。
按照说明，直接运行“bootstrap.bat...
biggest integer that can be stored in a double
...in IEEE 64-bit doubles without losing precision. An IEEE 64-bit double has 52 bits of mantissa, so I think it's 253:
253 + 1 cannot be stored, because the 1 at the start and the 1 at the end have too many zeros in between.
Anything less than 253 can be stored, with 52 bits explicitly stored in th...
Replace all non Alpha Numeric characters, New Lines, and multiple White Space with one Space
...-----------------
1,000 /[\W_]+/g 96,239.00 1.65 52,358.80 1.41
1,000 /[^a-z0-9]+/gi 97,584.40 1.18 52,105.00 1.60
1,000 /[^a-zA-Z0-9]+/g 96,965.80 1.10 51,864.60 1.76
---------------------------------------------------------------...
Unsupported major.minor version 52.0 [duplicate]
...hex)
Java SE 11 = 55 (0x37 hex)
Java SE 10 = 54
Java SE 9 = 53
Java SE 8 = 52
Java SE 7 = 51
Java SE 6.0 = 50
Java SE 5.0 = 49
JDK 1.4 = 48
JDK 1.3 = 47
JDK 1.2 = 46
JDK 1.1 = 45
These are the assigned major numbers. The error regarding the unsupported major.minor version is because during compile ...
PHP Timestamp into DateTime
...nstructor as-is:
// Assuming $item->pubDate is "Mon, 12 Dec 2011 21:17:52 +0000"
$dt = new DateTime($item->pubDate);
That being said, if you do have a timestamp that you wish to use instead of a string, you can do so using DateTime::setTimestamp():
$timestamp = strtotime('Mon, 12 Dec 2011 ...
Command to get nth line of STDOUT
...
From sed1line:
# print line number 52
sed -n '52p' # method 1
sed '52!d' # method 2
sed '52q;d' # method 3, efficient on large files
From awk1line:
# print line number 52
awk 'NR==52'
awk 'NR==52 {print;exi...
Remove unwanted parts from strings in a column
...ce it with.
pd.__version__
# '0.24.1'
df
time result
1 09:00 +52A
2 10:00 +62B
3 11:00 +44a
4 12:00 +30b
5 13:00 -110a
df['result'] = df['result'].str.replace(r'\D', '')
df
time result
1 09:00 52
2 10:00 62
3 11:00 44
4 12:00 30
5 13:00 110
...