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Dictionary vs Object - which is more efficient and why?
...sec obj=11sec dict=12sec namedtuple=16sec. I'm using CPython 2.6.6 on Win7 64bit
– Jonathan
Jul 5 '11 at 13:24
To emph...
What does “zend_mm_heap corrupted” mean
... 0x4C2F7E3: memcpy@@GLIBC_2.14 (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
==9749== by 0x40061B: main (an.c:13)
==9749== Address 0x50 is not stack'd, malloc'd or (recently) free'd
==9749==
==9749==
==9749== Process terminating with default action of signal 11 (SIGSEGV): dumping co...
C++11 range based loop: get item by value or reference to const
...answered Mar 2 '13 at 15:33
Mr.C64Mr.C64
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Best practices for SQL varchar column length [closed]
...n UK are usually between 1-35 characters. If you decide to make it varchar(64), you're not really going to hurt anything... unless you're storing this guy's family name that's said to be up to 666 characters long. In that case, maybe varchar(1028) makes more sense.
And in case it's helpful, here's ...
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...