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Quickest way to convert a base 10 number to any base in .NET?
...rbitrarySystem(long decimalNumber, int radix)
{
const int BitsInLong = 64;
const string Digits = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
if (radix < 2 || radix > Digits.Length)
throw new ArgumentException("The radix must be >= 2 and <= " + Digits.Length.ToString());
...
What is the difference between NaN and None?
...n reason to use NaN (over None) is that it can be stored with numpy's float64 dtype, rather than the less efficient object dtype, see NA type promotions.
# without forcing dtype it changes None to NaN!
s_bad = pd.Series([1, None], dtype=object)
s_good = pd.Series([1, np.nan])
In [13]: s_bad.dtype...
Is there a REAL performance difference between INT and VARCHAR primary keys?
...ring the test.
148.6 GB SSD drive, with plenty of free space.
Ubuntu 16.04 64-bit
MySQL Ver 14.14 Distrib 5.7.20, for Linux (x86_64)
The tables:
create table jan_int (data1 varchar(255), data2 int(10), myindex tinyint(4)) ENGINE=InnoDB;
create table jan_int_index (data1 varchar(255), data2 int(10...
Find the Smallest Integer Not in a List
...st in memory. In the form the question was asked, this would require O(N) 64-bit words.)
@Jorn comments that steps 1 through 3 are a variation on counting sort. In a sense he is right, but the differences are significant:
A counting sort requires an array of (at least) Xmax - Xmin counters wh...
What is the difference between a weak reference and an unowned reference?
...e: String) { self.name = name }
}
class CreditCard {
let number: UInt64
unowned let customer: Customer
init(number: UInt64, customer: Customer) { self.number = number; self.customer = customer }
}
In this example, a Customer may or may not have a CreditCard, but a CreditCard will alwa...
Is floating-point math consistent in C#? Can it be?
... I found this not easier than using integers directly.
Implement FixedPoint64 in C#. I found this rather hard to do. For some operations intermediate integers of 128bit would be useful. But .net doesn't offer such a type.
Implement a custom 32 bit floatingpoint. The lack of a BitScanReverse intrinsi...
jQuery selectors on custom data attributes using HTML5
...S: test was performed on MacOs High Sierra 10.13.3 on Chrome 67.0.3396.99 (64-bit), Safari 11.0.3 (13604.5.6), Firefox 59.0.2 (64-bit). Below screenshot shows results for fastest browser (Safari):
PureJS was faster than jQuery about 12% on Chrome, 21% on Firefox and 25% on Safari. Interestingly s...
What is a bank conflict? (Doing Cuda/OpenCL programming)
...d with a granuity of 32bit (so byte 0-3 are in bank 1, 4-7 in bank 2, ..., 64-69 in bank 1 and so on). For a better visualization it basically looks like this:
Bank | 1 | 2 | 3 |...
Address | 0 1 2 3 | 4 5 6 7 | 8 9 10 11 |...
Address | 64 65 66 67 | 68 69...
PHP CURL DELETE request
...
BolliBolli
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What are the advantages of NumPy over regular Python lists?
...ion cells -- neither approach would fit in a 32-bit architecture, but with 64-bit builds NumPy would get away with 4 GB or so, Python alone would need at least about 12 GB (lots of pointers which double in size) -- a much costlier piece of hardware!
The difference is mostly due to "indirectness" --...