I want to write library function in postgresql. Is it possible to write such function in .Net or I should use a special language like C to do this.
could you please show me a nice example or article about this?
thank you so much
According to the PostgreSQL procedural language matrix, there is no support for writing backend functions in .NET. But maybe one of the other languages listed there will suit you; it doesn't have to be C.
Related
Quick question (maybe).
I'm a process control engineer starting a new job with a company that uses Novatech software/hardware for SCADA and Operations. Novatech utilizes a programming language it calls SABL code. It looks very much like a hodge-podge between VB and Python. I'm trying to figure out if it's really just a base language adapted to their needs. What's throwing me off is it uses 'Else If' like VB but has mandatory indentation like Python. Is there a language that uses 'Else If' not 'elif' like Python or 'elsif' like Ruby but also has mandatory indentation?
If I can figure out the base language, I can put some study into the language and speed up my ability to use it proficiently. Otherwise, I'll end up in some class that's oriented on a lot of trifle information I don't need.
Any help would be appreciated.
Sequence And Batch Language (SABL®) is a proprietary language created by GSE Systems that was later purchased by Novatech. It is trademarked by Novatech and GSE. SABL® is based on (or conforms to) the ANSI/ISA-88 and ANSI/ISA-106 standards and is used in Novatech's D/3 Distributed Control System (DSP) software.
In other words, it does not have a base language and is much older than Python. It does conform to certain ISA standards but is solely used by one company who owns all rights and trademarks to it.
I would like to know which programming languages can be called by matlab.
for example I am quiet sure that matlab can use C function and maybe java.
I need this stuff for an industrial project so I need something that works well.
For example I have found some tutorial to call python function in matlab but they look to me not very good and stable solution.
I am not an expert of the field and my knowledge of matlab is very limited. So please be patience with the answer.
This project is related to machine learning and the software will probably run on a cluster.
EDIT according to this post Embedding Python in MATLAB seems that there are problem when importing numpy using python.
The only reason to use python in this environment is the numpy library.
Without that it is almost useless to me.
Do you think that I will encounter similar problem using java or c calling some mathematics libraries?
Most interfaces are listed here:
http://www.mathworks.de/de/help/matlab/external-interfaces.html
For Python I see different solutions:
COM on Windows platforms. This requires to register an application, check if this is possible and allowed on the cluster.
XMLRPC or SOAP. You may need to use Java-Classes in Matlab, but as you already realised this is very simple. Verify that the cluster has a Java VM available, many run matlab without java.
You can embed python code into c, which allows you to write mex functions which run c code: http://docs.python.org/2/extending/embedding.html
Use the command line interface for python.
Besides the documented limitations, I don't see any problem with these solution. If you are familiar with C or Matlab, I would choose the second or third option. This allows you to write a wrapper to access python with a very fundamental knowledge of matlab.
There are two main methods to achieve this:
Write MEX functions, which is basically C/C++ or Fortran methods, which use Matlab-specific API. You can then call these methods like you would any function written in M-language file. This is described here.
Call external libraries written in Java, .Net, C/C++, and COM servers. This is described here.
Both methods require good understanding of what you are doing, although I would argue that writing MEX function is much harder then referencing an existing library.
I'm not sure about programming language but You can do it by EXE file by running run('C:\someCompiledProgram.exe')
And if you need result you can use:
[status, result] = system('command')
You can read about it here:
http://nf.nci.org.au/facilities/software/Matlab/techdoc/ref/system.html
Given a Scala AST, is there a way to generate Scala source code?
I'm looking into ways to autogenerate Scala source by parsing/analyzing other Scala source. Any tips would be appreciated!
I have been successfully using Scala-Refactoring by Mirko Stocker for this task.
For synthetically constructing ASTs, it relies strongly on the existing Tree DSL of Scala's NSC.
Although the code is a bit messy, you can find an example usage in my project ScalaCollider-UGens.
I have also come across a very useful class by Johannes Rudolph.
See our DMS Software Reengineering Toolkit.
DMS provides a complete ecosystem for parsing/analyzing/optimizing/transforming source code in many languages. It achieves this by provide generic machinery for these tasks as its core capabilities, and specializing those according to explicitly supplied language definitions ("front ends"). DMS has front ends for many languages (C, C++, C#, Java, COBOL, ...) that have been used in anger, and a process for defining others very quickly.
We work on expanding the language set more or less continuously. DMS already has parts of a Scala front end implemented, and we know how to finish it based on the other 30+ front ends we have built, with special emphasis on knowledge of Java.
I realize that it is impossible to have one language that is best for everything.
But there is a class of simple programs, whose source code looks virtually identical in any language.
I am thinking not just "hello world", but also arithmetics, maybe string manipulation, basic stuff that you would typically see in utility classes.
I would like to keep my utilities in this meta-language and have it automatically translated to a bunch of popular languages. I do this by hand right now.
Again, I do not ask for translation of every single possible program. I am thinking a very limited, simple language, but superportable.
Do you know of anything like that? Is there a reason why it should not exist?
Check Haxe, and its Wikipedia page. It's open source and its main purpose is what you describe: generating code in many languages from only one source.
Just about any language that you choose is going to have some feature that doesn't map to another in a natural way. The closest thing I can think of is probably a useful subset of JavaScript. Of course, if you are the language author you can limit it as much as you want, providing only constructs that are common to just about any language (loops, conditionals, etc.)
For purposes of mutability, an XML representation would be best, but you wouldn't want to code in it.
If you find that there is no universal language, you can try a pragmatic model-driven development approach, using a template-based code generator.
On the template you keep the underlying concepts of an algorithm. Then, you would add code for this algorithm in one or more specific languages (C++,Java,JS,Python) when necessary. You would have to do it anyway, whatever the language or approach you choose. A configuration switch would pick the correct language for any template you apply.
AtomWeaver is a code generator that works with templates and employs ABSE as the modeling approach.
I did some looking and found this.
https://www.indiegogo.com/projects/universal-programming-language
looks interesting
A classic Pascal is very simple. Oberon is another similar option. Or you could invent your own derivative language similar to the pseudocode from the computer science textbooks. It's trivial to implement a translator from one of that languages into any decent modern imperative language.
I've been using NVelocity as a stand-alone templating engine in my text file generator. The problem with NVelocity is that the macros are quite shaky; pretty much all errors I get are from faulty macro implementation.
It would be cool if I could just use some other templating engine, such as Brail. That way I would just write functions that output strings.
What's the best way of embedding Brail engine? I would like to just pass it a string containing the template (not reading from disk), and I would like to minimize the number of external dependencies.
EDIT: I found the answer myself. Take a look at this source file from Castle.
Try nHaml or Spark as they both support full standalone or direct usage
They both support standard c# functions that return strings etc
Spark is real HTML, nHaml is DRY HTML
Both very cool!