i do not know what numerical rational testing is, but the [expr] object has a basic if else function.
from the helpfile:

you can also build something with [spigot].

a bit off-topic: and this is a nice way to convert symbols to lists while the example above converts lists to symbols.

just discovered recently that [fudiformat] and [fudiparse] are part of pd vanilla for some time.

this does work for displaying messages including spaces too (i also get the errors mentioned by @ingox):

and on windows i can open files with spaces with [readsf~] too.

the console prints: "parse-output: [:tuw <300 \, 10>]", i do not know if that helps.

[fudiparse] is part of vanilla since summer 2017 (PD 0.48.0). i also did not know. very useful (always used some other solutions).

@whale-av thanks, everything works fine. I was just wondering if every PD instance needs its own port. obviously not if it receives udp, thanks for your explanations.

@whale-av thanks a lot for your explanations, i think i understand the netsend object better now. and it works with multiple pd instances. it seems that each pd instance needs its own port?
pdtexttospeechwindows.zip
this ist the gui instance:

and this are two of the netreceive instances:

I recognized one problem: while the text to speech command prompt is running via [sytem], the pure data patch is "frozen". is there a way to solve it (then I can play for example a female and a male voice together)?
I also tried the [sys_gui] method: https://forum.pdpatchrepo.info/topic/10168/is-it-possible-to-execute-an-exe-from-within-puredata/10
But somehow I can not execute an .exe file with it (message to [sys_gui] : exec "path to .exe")...

it does work now on windows with this tool: https://www.elifulkerson.com/projects/commandline-text-to-speech.php
and the [sytem] object from the motex library.
with this python code:

import speech_recognition as sr
import socket
s = socket.socket()
host = socket.gethostname()
port = 3000
s.connect((host, port))

while (True == True):
  r = sr.Recognizer()
  with sr.Microphone() as source:
    r.adjust_for_ambient_noise(source, duration = 1)
    print("Say something!")
    audio = r.listen(source,phrase_time_limit = 5)
 
  try:
    pdMessage = r.recognize_google(audio, language = "en-US") + " ;"
    message = r.recognize_google(audio, language = "en-US")
    s.send(pdMessage.encode('utf-8'))
    print("PD Message: " + message)
  except sr.UnknownValueError:
    print("Google could not understand audio")
  except sr.RequestError as e:
    print("Google error; {0}".format(e))

and this patch: speechtoquote.pd
here is the csv file that I used: https://github.com/akhiltak/inspirational-quotes/blob/master/Quotes.csv

@Johnny-Mauser exactly that (even if it is not a real world project (yet) but discovering the possibilities of speech recognition and pure data). I can probably transfer it to Windows if you (or somebody else) can give me some more hints how that is done with Pure Data and OSX. That is what i found about speech recognition and OSX in the mailing list: https://www.mail-archive.com/pd-list@iem.at/msg45054.html