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Using i and j as variables in Matlab
.../i.html
http://www.mathworks.co.uk/help/matlab/ref/j.html
So a variable called i or j will override them, potentially silently breaking code that does complex maths.
Possible solutions include using ii and jj as loop variables instead, or using 1i whenever i is required to represent the imaginary...
hidden symbol ... is referenced by DSO 剖析 - C/C++ - 清泛网 - 专注C/C++及内核技术
...用如下代码即可兼容Win/Linux平台的函数导出：
#ifdef WIN32
#ifdef XXX_EXPORTS
#define XXX_API __declspace(dllexport)
#else
#define XXX_API __declspace(dllimport)
#endif
#define XXX_LOCAL
#else
#ifdef XXX_EXPORTS
#define XXX_API __attribute__ ((visibility("defaul...
Postgres: INSERT if does not exist already
... if one modifies the table such that more columns are unique. In that case all the scripts must be modified. It would be nice if there was a more generic way to do this...
– Willem Van Onsem
Aug 1 '14 at 13:17
...
How to slice an array in Bash
...
There is also a convenient shortcut to get all elements of the array starting with specified index. For example "${A[@]:1}" would be the "tail" of the array, that is the array without its first element.
version=4.7.1
A=( ${version//\./ } )
echo "${A[@]}" # 4 7 1
B...
Authentication versus Authorization
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Authentication is the process of ascertaining that somebody really is who they claim to be.
Authorization refers to rules that determine who is allowed to do what. E.g. Adam may be authorized to create and delete databases,
while Usama is only authorised to read.
The two concep...
ERROR: permission denied for sequence cities_id_seq using Postgres
I'm new at postgres (and at database info systems all in all). I ran following sql script on my database:
4 Answers
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Setting unique Constraint with fluent API?
I'm trying to build an EF Entity with Code First, and an EntityTypeConfiguration using fluent API. creating primary keys is easy but not so with a Unique Constraint. I was seeing old posts that suggested executing native SQL commands for this, but that seem to defeat the purpose. is this possible ...
How can I use a local image as the base image with a dockerfile?
...ockerfile.
I just realised that I've been using FROM with indexed images all along.
4 Answers
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Cleaner way to update nested structures
...scalaz.TreeLoc). It turns out that the structure of the zipper is automatically derivable from the original data structure, in a manner that resembles symbolic differentiation of an algebraic expression.
But how does this help you with your Scala case classes? Well, Lukas Rytz recently prototyped a...
Stopwatch vs. using System.DateTime.Now for timing events [duplicate]
...time by counting timer ticks in the underlying timer mechanism. If the installed hardware and operating system support a high-resolution performance counter, then the Stopwatch class uses that counter to measure elapsed time. Otherwise, the Stopwatch class uses the system timer to measure elapsed ti...