Help with applying this instrument monitoring code to multiple inputs. - Printable Version +- Python Forum (https://python-forum.io) +-- Forum: Python Coding (https://python-forum.io/forum-7.html) +--- Forum: General Coding Help (https://python-forum.io/forum-8.html) +--- Thread: Help with applying this instrument monitoring code to multiple inputs. (/thread-24765.html) |
Help with applying this instrument monitoring code to multiple inputs. - Kid_Meier - Mar-03-2020 Hello, world. I have some working code (below) that communicates with a pressure gauge, takes the reading, saves it to a log file, and displays a live plot. I am hoping that someone is willing to help with rewriting it so that I can neatly apply it to my other gauges. Right now I have a single plot, and I output a log file with two columns (time and pressure). I think that what I want is to have a function inside the animation loop that takes in instrumentID and "Title" as inputs, and maybe add an argument to the whole script that tells it how many gauges I have and how to arrange the subplots. That last bit might be dumb though? Extra credit (I would be super appreciative if you help with these, but don't feel that you need to, to help with the above): 1) I've seen in other forum posts that I should be using "return line," instead of plt.draw(), but I can't seem to get that to display my datetime axis properly, if it works at all. Should I change it to this? If so, how? 2) I'd like to add a header line to the log file. This has made me realize I have a problem, though. What happens if I start the program with (GaugeA, GaugeB, GaugeC), then close it and reopen later with (GaugeB, GaugeA, GaugeD). This seems like a serious problem. 3) Also, just in general, it should be obvious that I am a total n00b. I would appreciate comments on how to write this code better in general (e.g. variable naming, order of operations, etc) My thanks in advance, Mike import visa from datetime import datetime import time import numpy as np import matplotlib.pyplot as plt import matplotlib.animation as animation fig, (ax1) = plt.subplots(1, 1) #------------------------------------------------------- date = datetime.today().strftime('%Y-%m-%d') + '.txt' logfile = open(date,'a') # Create or open a log file with today's date rm = visa.ResourceManager() # Open up the visa RM that looks for connected instruments CapGauge = rm.open_resource('ASRL3::INSTR') # Open up the specific instrument I care about CapGauge.read_termination = '\r\n' # Fix the terminations so that I get a response at all CapGauge.write_termination = '\r\n' #------------------------------------------------------- x = [] y = [] def animate(i): # This is the animation loop for my live plot current_time = datetime.now().strftime("%H:%M:%S") # Format the date how I like it CapGauge.query('PR1') # I send the query to the instrument asking for Pressue Reading on gauge 1 # The instrument then replies with "\x06\x13\x10" (ACKNOWLEDGE CR LF) # Or, if reading is unsuccessful, "\x15\x13\x10" (NEGATIVE ACKNOWLEDGE CR LF) tempstr = CapGauge.query('\x05') # Then I send the "\x05" (ENQUIRY) character if len(tempstr)>1: # This catches the junk feedback lines that happen sometimes because I'm a bad programmer tempstr = tempstr.split(',')[1] # The gauge sends a string with format "a,sxx.xxxxEsxx" # where a is a status integer, s is a sign, and sxx.xxxxEsxx is my pressure reading x.append(datetime.now().replace(microsecond=0)) # I strip away the microseconds here just coz they annoy me, but I keep the datetime format y.append(float(tempstr)) # Turn the pressure reading string into a float logfile.write(current_time + '\t') # Write it to my log file as well logfile.write(tempstr + '\n') logfile.flush() # Save my logfile so that I don't lose the data if something goes wrong ax1.clear() # Clear the axes ax1.plot(x,y) # Plot the data (including the newly appended point) ax1.set_title("Capacitance Manometer") # Make the live plot look nice ax1.set_xlabel("Time") # Make the live plot look nice ax1.set_ylabel("Pressure (mbar)") # Make the live plot look nice time.sleep(0.5) # Wait to take the next data point plt.draw() # I admit I'm not at all clear on what plt.draw() does, vs ax1.plot() and plt.show() anim = animation.FuncAnimation(fig, animate, frames = 200, interval = 20) # Do the animation plt.show() # Show the plot CapGauge.close() logfile.close() raise SystemExit RE: Help with applying this instrument monitoring code to multiple inputs. - Kid_Meier - Mar-04-2020 Okay, this is how far I've gotten (see below). I decided to make a Class called "Instrument" that initializes with the instrumentID, the name string I want for the instrument, and empty lists for x-y coords for the plot. It also takes in the necessary terminator string which is different for a few of the gauges I have, as well as a type (manufacturer) identifier to tell it what comms protocol to use, because that, again, is different between the different gauge types. The Instrument class also has an update method which does the pressure reading query, adds the new data to the plot, and writes it to the log file, preceded by a tab. This way, in the animate loop, I can write the current time to the log file, then iterate through a list of all the gauges I have active, running the update and then plotting. I also made an init function for the animate loop that writes the header line I wanted, using the name property from each Instrument. Comments would be greatly appreciated. Thanks, Mike import visa from datetime import datetime import time import numpy as np import matplotlib.pyplot as plt import matplotlib.animation as animation class Instrument: def __init__(self, InstrumentIdentifierString, InstrumentName, terminator, type): global rm self.title = InstrumentName self.type = type self.ID = rm.open_resource(InstrumentIdentifierString) self.ID.read_termination = terminator self.ID.write_termination = terminator self.x = [] self.y = [] def update(self): global logfile tempstr = "" counter = 0 while len(tempstr)<1: if self.type == "Pfeiffer": self.ID.query('PR1') tempstr = self.ID.query('\x05') elif self.type == "Jevatec": tempstr = self.ID.query('RPV\x2C1') counter += 1 if counter = 10: tempstr = " ,'----------" tempstr = tempstr.split(',')[1] self.x.append(datetime.now().replace(microsecond=0)) self.y.append(float(tempstr)) logfile.write('\t' + tempstr) def animinit(GaugeList): global logfile global fig global axlist logfile.write("# Time") for iter,instr in enumerate(GaugeList): axlist[0][iter].set_title(instr.title) axlist[0][iter].set_xlabel("Time") axlist[0][iter].set_ylabel("Pressure(mbar)") logfile.write('\t "' + instr.title + '"') logfile.write('\n') logfile.flush() def animate(i, GaugeList): current_time = datetime.now().strftime("%H:%M:%S") logfile.write(current_time) for iter,instr in enumerate(GaugeList): instr.update() axlist[0][iter].clear() axlist[0][iter].plot(instr.x,instr.y) logfile.write('\n') logfile.flush() time.sleep(60) plt.draw() date = datetime.today().strftime('%Y-%m-%d--%Hh-%Mm') + '.txt' logfile = open(date,'a') # Create or open a log file with today's date rm = visa.ResourceManager() # Open up the visa RM that looks for connected instruments GaugeList = [] GaugeList.append(Instrument('ASRL4::INSTR','Analysis Chamber','\r\n','Pfeiffer')) #GaugeList.append(Instrument('ASRL5::INSTR','Detector','\r','Jevatec')) fig,axlist = plt.subplots(1, len(GaugeList),squeeze=False) anim = animation.FuncAnimation(fig, animate, frames=200, init_func=animinit(GaugeList), fargs=(GaugeList,), interval=20) # Do the animation plt.show() # Show the plot for instr in GaugeList: instr.ID.close() logfile.close() raise SystemExit |