DHT11 Sensor with RPI
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hello, i am currently working on my side hobby. im fairly new with pyqt, and im stuck in this step for quite sometime. ive created a UI showing the temperature and humidity. i wanted to show more. i want to display a graph on the UI which logs the temperature and humidity every 20 minutes, plotting the average of 20 mins. ive known about plotwidget and matplotlib, but i still cant figure out on how to get the data and draw out the graph. im kinda new to this whole thing. please do be patient with me im just a kid that needs help thanks in advanced !
this is the code i currently have
import Adafruit_DHT import time from PyQt5 import QtCore, QtGui, QtWidgets from PyQt5.QtCore import * from pyqtgraph import PlotWidget sensor = Adafruit_DHT.DHT11 pin = 4 class Ui_Dialog(object): def setupUi(self, Dialog): Dialog.setObjectName("Dialog") Dialog.resize(634, 428) self.lcdNumber = QtWidgets.QLCDNumber(Dialog) self.lcdNumber.setGeometry(QtCore.QRect(220, 40, 271, 131)) self.lcdNumber.setObjectName("lcdNumber") self.lcdNumber_2 = QtWidgets.QLCDNumber(Dialog) self.lcdNumber_2.setGeometry(QtCore.QRect(220, 200, 271, 131)) self.lcdNumber_2.setObjectName("lcdNumber_2") self.label = QtWidgets.QLabel(Dialog) self.label.setGeometry(QtCore.QRect(26, 42, 161, 131)) font = QtGui.QFont() font.setPointSize(16) self.label.setFont(font) self.label.setObjectName("label") self.label_2 = QtWidgets.QLabel(Dialog) self.label_2.setGeometry(QtCore.QRect(30, 190, 161, 131)) font = QtGui.QFont() font.setPointSize(16) self.label_2.setFont(font) self.label_2.setObjectName("label_2") self.widget = PlotWidget(Dialog) self.widget.setGeometry(QtCore.QRect(510, 40, 391, 131)) self.widget.setObjectName("widget") self.widget_2 = PlotWidget(Dialog) self.widget_2.setGeometry(QtCore.QRect(510, 200, 391, 131)) self.widget_2.setObjectName("widget_2") self.timer = QTimer() self.timer.setInterval(5000) self.timer.timeout.connect(self.DHTread) self.timer.start() self.retranslateUi(Dialog) QtCore.QMetaObject.connectSlotsByName(Dialog) def retranslateUi(self, Dialog): _translate = QtCore.QCoreApplication.translate Dialog.setWindowTitle(_translate("Dialog", "Dialog")) self.label.setText(_translate("Dialog", "Temperature :")) self.label_2.setText(_translate("Dialog", "Humidity :")) def DHTread(self): humidity, temperature = Adafruit_DHT.read_retry(sensor,pin) print('Temp =', temperature,'*C Humidity =', humidity) self.lcdNumber.display(temperature) self.lcdNumber_2.display(humidity) if __name__ == "__main__": import sys app = QtWidgets.QApplication(sys.argv) Dialog = QtWidgets.QDialog() ui = Ui_Dialog() ui.setupUi(Dialog) Dialog.show() sys.exit(app.exec_())@helloworldddd What exactly does not work? Is DHTread(self) called? If so, what does it print?
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@helloworldddd What exactly does not work? Is DHTread(self) called? If so, what does it print?
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@jsulm i cant figure out on how to plot a graph and display it with PlotWidget and pyqtgraph with the values taken from the sensor !
@helloworldddd I never used PlotWidget or pyqtgraph and those are not part of Qt.
You should consider reading some documentation/tutorial like https://www.learnpyqt.com/courses/graphics-plotting/plotting-pyqtgraph/
Or check https://doc.qt.io/qt-5/qtcharts-index.html which is part of Qt. -
@helloworldddd I never used PlotWidget or pyqtgraph and those are not part of Qt.
You should consider reading some documentation/tutorial like https://www.learnpyqt.com/courses/graphics-plotting/plotting-pyqtgraph/
Or check https://doc.qt.io/qt-5/qtcharts-index.html which is part of Qt. -
@jsulm ive also read up on using .csv files to plot the graph by using the values recorded. the examples shown were only fixed values. how do i plot the graph with values that just being recorded ?
@helloworldddd said in DHT11 Sensor with RPI:
how do i plot the graph with values that just being recorded ?
Well, use the recorded values instead of the values from csv. I really don't get what exactly the problem is! Can you please be more specific?
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@helloworldddd said in DHT11 Sensor with RPI:
how do i plot the graph with values that just being recorded ?
Well, use the recorded values instead of the values from csv. I really don't get what exactly the problem is! Can you please be more specific?
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@jsulm how do i get the recorded values and put it into a list and limit the list to like in 2 hour intervals with 20 mins as every point. and the time, which is the x axis to self increment?
@helloworldddd said in DHT11 Sensor with RPI:
how do i get the recorded values and put it into a list and limit the list to like in 2 hour intervals with 20 mins as every point
What is your level of experience with programming? Do you know how you can add values to a list in Python? Please don't forget that this is Qt forum not Python... "limit the list to like in 2 hour intervals with 20 mins" - this is simple math to calculate how many elements the list should contain (max).
You never answered my question: "Is DHTread(self) called? If so, what does it print?" Can you please answer it?
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@helloworldddd said in DHT11 Sensor with RPI:
how do i get the recorded values and put it into a list and limit the list to like in 2 hour intervals with 20 mins as every point
What is your level of experience with programming? Do you know how you can add values to a list in Python? Please don't forget that this is Qt forum not Python... "limit the list to like in 2 hour intervals with 20 mins" - this is simple math to calculate how many elements the list should contain (max).
You never answered my question: "Is DHTread(self) called? If so, what does it print?" Can you please answer it?
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@jsulm like i said im just a newbie with programming. was hoping to find some help here. which incase guess i came to the wrong place. DHTread(self) is called. it just shows the value onto the UI through lcdnumber display
@helloworldddd said in DHT11 Sensor with RPI:
DHTread(self) is called
That is good. Now you can add the values to a list (myList.append(myValue)). But it is better to use https://www.oreilly.com/library/view/python-cookbook/0596001673/ch05s19.html in your case as you want to have a list with fixed max size and remove old values if you insert new values into full list.
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@helloworldddd said in DHT11 Sensor with RPI:
DHTread(self) is called
That is good. Now you can add the values to a list (myList.append(myValue)). But it is better to use https://www.oreilly.com/library/view/python-cookbook/0596001673/ch05s19.html in your case as you want to have a list with fixed max size and remove old values if you insert new values into full list.
@jsulm ahhh u could have started with that but thanks so much for your help !
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@helloworldddd said in DHT11 Sensor with RPI:
DHTread(self) is called
That is good. Now you can add the values to a list (myList.append(myValue)). But it is better to use https://www.oreilly.com/library/view/python-cookbook/0596001673/ch05s19.html in your case as you want to have a list with fixed max size and remove old values if you insert new values into full list.
@jsulm hello, sorry to bother u again. do u know how to use plot values to time, time as x axis on pyqtgraph? im using the command self.widget.plot() i would like to input the x axis value as time instead of a list of number like below. Thanks in advance !
hour = [1,2,3,4,5,6,7,8,9,10] reading = [] #this is the reading from the sensor self.widget.plot(hour, reading) -
@jsulm hello, sorry to bother u again. do u know how to use plot values to time, time as x axis on pyqtgraph? im using the command self.widget.plot() i would like to input the x axis value as time instead of a list of number like below. Thanks in advance !
hour = [1,2,3,4,5,6,7,8,9,10] reading = [] #this is the reading from the sensor self.widget.plot(hour, reading)@helloworldddd said in DHT11 Sensor with RPI:
do u know how to use plot values to time, time as x axis on pyqtgraph?
Sorry, I never used pyqtgraph. Did you check its documentation?
