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Select random row from a sqlite table
...gt; select count(*) from payment;
16049
Run Time: real 0.000 user 0.000140 sys 0.000117
sqlite> select payment_id from payment limit 1 offset abs(random()) % (select count(*) from payment);
14746
Run Time: real 0.002 user 0.000899 sys 0.000132
sqlite> select payment_id from payment limit 1 of...
Are C++ enums signed or unsigned?
...operands using the < operator, we are actually talking about implicitly converting the enum type to some integral type. It is the sign of this integral type that matters. And when converting enum to integral type, this statement applies:
9 The value of an enumerator or an object of an enumeratio...
How to convert a Java 8 Stream to an Array?
What is the easiest/shortest way to convert a Java 8 Stream into an array?
10 Answers
...
What do the python file extensions, .pyc .pyd .pyo stand for?
...mode, without a console; executed with pythonw.exe
.pyx - Cython src to be converted to C/C++
.pyd - Python script made as a Windows DLL
.pxd - Cython script which is equivalent to a C/C++ header
.pxi - MyPy stub
.pyi - Stub file (PEP 484)
.pyz - Python script archive (PEP 441); this is a script con...
how to convert array values from string to int?
returns
14 Answers
14
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Can we define implicit conversions of enums in c#?
...ic static implicit operator AccountStatus(byte value)
{
return Convert(value);
}
}
The base class (RichEnum) is listed below.
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Diagnostics;
using System.Linq;
using System.Reflection;
using Sy...
Cast List to List in .NET 2.0
...
.NET 2.0 has the ConvertAll method where you can pass in a converter function:
List<int> l1 = new List<int>(new int[] { 1, 2, 3 } );
List<string> l2 = l1.ConvertAll<string>(delegate(int i) { return i.ToString(); })...
Android and setting width and height programmatically in dp units
...
You'll have to convert it from dps to pixels using the display scale factor.
final float scale = getContext().getResources().getDisplayMetrics().density;
int pixels = (int) (dps * scale + 0.5f);
...
CSV in Python adding an extra carriage return, on Windows
... CSV writer. Also, it doesn't address the issue if the script wants to use sys.stdout as the stream.
I suggest instead setting the 'lineterminator' attribute when creating the writer:
import csv
import sys
doc = csv.writer(sys.stdout, lineterminator='\n')
doc.writerow('abc')
doc.writerow(range(3)...
How to convert integer to string in C? [duplicate]
I tried this example:
3 Answers
3
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