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c# and libraries from python

Does C# have a library that can reproduce the same thing?
from tensorflow import keras
from tensorflow.keras import layers
Functions to reproduce:
# A utility function to decode the output of the network
def decode_batch_predictions(pred):
input_len = np.ones(pred.shape[0]) * pred.shape[1]
# Use greedy search. For complex tasks, you can use beam search
results = keras.backend.ctc_decode(pred, input_length=input_len, greedy=True)[0][0][:, :max_length]
# Iterate over the results and get back the text
output_text = []
for res in results:
res = tf.strings.reduce_join(num_to_char(res)).numpy().decode("utf-8")
output_text.append(res)
return output_text
The situation is as follows. I trained the model, it works fine. But I haven 't found a way to decode the model 's response in the environment yet .NET ;(
I will be grateful for any help.

C# - Python interop using Python.Net [No module named '_ctypes']

I am trying to use Python.NET to perform interop between C# and Python on a Windows machine.
Specifically I have the following code.
PythonEngine.PythonHome = #"C:\Python\3_5_4";
PythonEngine.PythonPath = #"C:\Python\3_5_4\Lib;C:\Python\3_5_4\Lib\site-packages";
using (Python.Runtime.Py.GIL())
{
dynamic np = Py.Import("numpy");
dynamic sin = np.sin;
Console.WriteLine(sin);
}
While I can successfully execute a general python statement as such:
var res = PythonEngine.Eval("1 + 1");
Console.WriteLine(res);
//res = 2
Which indicates that the python engine itself is working successfully, I can also invoke something like this:
var html = Py.Import("html");
Console.WriteLine(html);
//html = <module 'html' from 'C:\\Python\\3_5_4\\Lib\\html\\__init__.py'>
Which further indicates that the module loading functionality is also working correctly.
However whenever I attempt to invoke the line:
dynamic np = Py.Import("numpy");
I receive the following error:
{"ImportError : No module named '_ctypes'"}.
[' File "C:\\Python\\3_5_4\\Lib\\site-packages\\numpy\\__init__.py", line 140, in <module>\n from . import _distributor_init\n', ' File "C:\\Python\\3_5_4\\Lib\\site-packages\\numpy\\_distributor_init.py", line 9, in <module>\n from ctypes import WinDLL\n', ' File "C:\\Python\\3_5_4\\Lib\\ctypes\\__init__.py", line 8, in <module>\n from _ctypes import Union, Structure, Array\n']
The file referenced is located # 'C:\Python\3_5_4\Lib\ctypes\__init__.py'.
I have verified that all the expected paths are set correctly and that the Ctypes folder exists in my python path.
I have tried everything from uninstalling and reinstalling Python to modifying the ctypes/__init__.py file to try and import Ctypes directly to no effect.
Having researched this topic online throughly I have found a number of suggestions which point to running yum install libffi-devel as detailed here. However this does not appear to be something that I can perform on windows given that yum appears to be a Linux only application.
Can anyone provide any guidance?

How do I run an external python script that's importing 3rd party library himself, in C#?

I was trying to combine a Python code with C#, to use all those cool libraries like Speech Recognition inside my C# application.
I made two different projects one for python (IronPython) where I've included the module I need (Speech Recognition) through the python environment in VS2017 and the other one is just a console application where I want to call this app.
I thought the point was to change the searchPaths of Ironpython and afterwards it'll work.
Maybe I'm doing something wrong or maybe it just shouldn't work anyway?
C# Code Main.cs:
using IronPython.Hosting;
using System.Collections.Generic;
private static void Main(string[] args)
{
//Using Iron python
var engine = IronPython.Hosting.Python.CreateEngine();
System.Console.WriteLine("Search paths:");
ICollection<string> searchPaths = engine.GetSearchPaths();
foreach (string path in searchPaths)
{
System.Console.WriteLine(path);
}
System.Console.WriteLine();
searchPaths.Add("..\\..");
///Trying to add a searchPath for the place with the module I need
searchPaths.Add(#"C:\Program Files (x86)\Microsoft Visual
Studio\Shared\Anaconda3_64\Lib\site-packages");
engine.SetSearchPaths(searchPaths);
var res = engine.CreateScriptSourceFromFile(
#"D:\Python\Projects\TestSpeechRecognition
\TestForNETinPython\TestForNETinPython.py"
);
engine.ImportModule("speech_recognition");
var result = res.Execute();
}
Python code
import speech_recognition as sr
r = sr.Recognizer()
with sr.Microphone() as source:
print ("Hello: ")
audio = r.listen(source)
try:
print ("I said: " + r.recognize_google(audio))
except sr.UnknownValueError:
print ("Cant't rec")
except sr.RequestError as e:
print ("Can't connect: (0)".format(e))
Exception:
Unhandled Exception:
IronPython.Runtime.Exceptions.ImportException: no module named speech_recognition
at IronPython.Hosting.PythonService.ImportModule(ScriptEngine engine, String name)
at IronPython.Hosting.Python.ImportModule(ScriptEngine engine, String moduleName)
at Test.Program.Main(String[] args) in D:\Python\Projects\TestSpeechRecognition\Test\Program.cs:line 26
I even read some literature about creating the modules like this one http://www.needfulsoftware.com/IronPython/IronPythonCS2 or this one it's for pythonnet and a little bit creepy, but I guess it may be useful (NoteBook).
Hope someone can use it to solve the problem.

Communication between Python and C#

I have a Python backend running machine learning algorithms. I want to use the same backend for both an Excel plugin (C#) and a website. I want both interfaces to send my training data (thousands of lines of numbers in arrays) to the same Python application and retrieve the results in the form of another array up to a few thousand lines.
The website would fetch data from a SQL database and send that data to Python, while the Excel plugin would take the data that is in the current worksheet and send that data to Python. I need to be able to create numpy arrays in Python before continuing to process the data. Note that the website would be running on the same machine where the Python application resides. I still haven't decided what I will use to code the website, but I was leaning towards Node.js.
I have done some research and found a few options:
1- Named pipes
2- Sockets
3- RPC server such as gRPC or XML-RPC.
4- Writing the data to a file and reading it back in Python
5- Web Service
Note: I would need the Python "server" to be stateful and keep the session running between calls. So I would need to have a kind of daemon running, waiting for calls.
Which one would you experts recommend and why? I need flexibility to handle several parameters and also large arrays of numbers. Using IronPython is not an option because I am running Keras on Python, which apparently does not support IronPython.

I had the same problem recently.
I used a named pipe to transport data from python to my c# server, hope it helps you.
Python:
import win32pipe, win32file
class PipeServer():
def __init__(self, pipeName):
self.pipe = win32pipe.CreateNamedPipe(
r'\\.\pipe\\'+pipeName,
win32pipe.PIPE_ACCESS_OUTBOUND,
win32pipe.PIPE_TYPE_MESSAGE | win32pipe.PIPE_READMODE_MESSAGE | win32pipe.PIPE_WAIT,
1, 65536, 65536,
0,
None)
#Carefull, this blocks until a connection is established
def connect(self):
win32pipe.ConnectNamedPipe(self.pipe, None)
#Message without tailing '\n'
def write(self, message):
win32file.WriteFile(self.pipe, message.encode()+b'\n')
def close(self):
win32file.CloseHandle(self.pipe)
t = PipeServer("CSServer")
t.connect()
t.write("Hello from Python :)")
t.write("Closing now...")
t.close()
For this code to work you need to install pywin32 (best choice is from binarys): https://github.com/mhammond/pywin32
C#-Server:
using System;
using System.IO;
using System.IO.Pipes;
class PipeClient
{
static void Main(string[] args)
{
using (NamedPipeClientStream pipeClient =
new NamedPipeClientStream(".", "CSServer", PipeDirection.In))
{
// Connect to the pipe or wait until the pipe is available.
Console.Write("Attempting to connect to pipe...");
pipeClient.Connect();
Console.WriteLine("Connected to pipe.");
Console.WriteLine("There are currently {0} pipe server instances open.",
pipeClient.NumberOfServerInstances);
using (StreamReader sr = new StreamReader(pipeClient))
{
// Display the read text to the console
string temp;
while ((temp = sr.ReadLine()) != null)
{
Console.WriteLine("Received from server: {0}", temp);
}
}
}
Console.Write("Press Enter to continue...");
Console.ReadLine();
}
}

You can use Python for .NET (Python.NET). It may require some changes to your code, but then it should work very well, once everything is in good shape.
Python.NET allows two-way communication between CPython and CLR.

Let me give you a neat and quick recipe, in the form of example code.
There are basically two ways to tie python in the backend of C# (or a C# winform app or gui or something similar).
Method1: Iron Python. In this method you install a .net package in your visual studio called IronPython. I would not prefer this, because assuming your machine learning model uses keras or a lot of other libraries. It would be another quest to get you installations ready and working in IronPython. And most importantly, it is not as good as your common virtual env or conda environment.
Method2: (The Good Method): Create a Custom Process in your C# that takes arguments from your GUI, knows the path to your script and your python env. Using all these things, it calls your python code exactly the way you would call it in your terminal and pass arguments to it.
Now the tasty example code (I have used this simple trick and it always helps make my black screen python stuff look good with the cover of C# apps).
Python Part
import sys
a = sys.argv[1]
b = sys.argv[2]
print("The Sum = ", float(a)+float(b))
The C# Part
So here is the python process/function that you need to call on the click event of your sum button in the application
static void PythonProcess()
{
//1) Create Process Info
var psi = new ProcessStartInfo();
//Conda Env Path
psi.FileName = #"C:\Users\jd\.conda\pkgs\py\python.exe";
//2) Provide Script and the Arguments
var script = #"C:\Users\jd\Desktop\script.py";
var a = "15";
var b = "18";
psi.Arguments = $"\"{script}\" \"{a}\" \"{b}\"";
//3) Process Configuration
psi.UseShellExecute = false;
psi.CreateNoWindow = true;
psi.RedirectStandardOutput = true;
psi.RedirectStandardError = true;
//4) Execute Process and get Output.
var errors = "";
var results = "";
using(var process = Process.Start(psi))
{
errors = process.StandardError.ReadToEnd();
results = process.StandardOutput.ReadToEnd();
}
//5) Display Output
Console.WriteLine("ERRORS: ");
Console.WriteLine(errors);
Console.WriteLine();
Console.WriteLine("RESULTS: ");
Console.WriteLine(results);
}

Calling Python from C# is easily possible via Pyrolite where your Python code is running as a Pyro4 server. It should be fast enough to handle "large arrays of numbers" however you didn't specify any performance constraints.

I had the same issue and seem to end up with named pipes. Here is a nice example of how to set it up to talk C# => Python, assuming C# is the server.
It can use the same way to talk back or just Python.net to call directly through CLR as shown here. I use the latter.

How do I call a specific Method from a Python Script in C#?

I'm wondering if there is a possibility to call a specific Method from a Python script over a C# project.
I have no code... but my idea is:
Python Code:
def SetHostInfos(Host,IP,Password):
Work to do...
def CalcAdd(Numb1,Numb2):
Work to do...
C# Code:
SetHostInfos("test","0.0.0.0","PWD")
result = CalcAdd(12,13)
How can I call one of the Methods, from this Python script, over C#?

You can host IronPython, execute the script and access the functions defined within the script through the created scope.
The following sample shows the basic concept and two ways of using the function from C#.
var pySrc =
#"def CalcAdd(Numb1, Numb2):
return Numb1 + Numb2";
// host python and execute script
var engine = IronPython.Hosting.Python.CreateEngine();
var scope = engine.CreateScope();
engine.Execute(pySrc, scope);
// get function and dynamically invoke
var calcAdd = scope.GetVariable("CalcAdd");
var result = calcAdd(34, 8); // returns 42 (Int32)
// get function with a strongly typed signature
var calcAddTyped = scope.GetVariable<Func<decimal, decimal, decimal>>("CalcAdd");
var resultTyped = calcAddTyped(5, 7); // returns 12m

I found a similar way to do it, the call of the method is much easier with it.
C# Code goes as follows:
IDictionary<string, object> options = new Dictionary<string, object>();
options["Arguments"] = new [] {"C:\Program Files (x86)\IronPython 2.7\Lib", "bar"};
var ipy = Python.CreateRuntime(options);
dynamic Python_File = ipy.UseFile("test.py");
Python_File.MethodCall("test");
So basically I submit the Dictionary with the Library path which I want to define in my python file.
So the PYthon Script looks as follows:
#!/usr/bin/python
import sys
path = sys.argv[0] #1 argument given is a string for the path
sys.path.append(path)
import httplib
import urllib
import string
def MethodCall(OutputString):
print Outputstring
So The method call is now much easier from C#
And the argument passing stays the same.
Also with this code you are able to get a custom library folder
for the Python file which is very nice if you work in a network
with a lot of different PC's

You could make your python program take arguments on the command line then call it as a command line app from your C# code.
If that's the way to go then there are plenty of resources:
How do I run a Python script from C#?
http://blogs.msdn.com/b/charlie/archive/2009/10/25/hosting-ironpython-in-a-c-4-0-program.aspx