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KeyError: 2 - stsxbel - Aug-16-2022
Good evening, the second day I struggle with the code, then there is no entry in the database, then the error is KeyError: 2
import struct
import sys
import time
import datetime
import pymysql.cursors
from pymodbus.client.sync import ModbusSerialClient
from pymodbus.exceptions import ModbusIOException
from datetime import datetime
connection = pymysql.connect(host='127.0.0.1', user='root', password='passwd', db='scales', charset='utf8mb4', cursorclass=pymysql.cursors.DictCursor)
unit = 5
client = ModbusSerialClient(method='rtu', port='/dev/ttyUSB1', parity='N', baudrate=9600, bytesize=8, stopbits=1, timeout=1, strict=False)
#---------------------------Продукт 1-------------------------
while True:
reply = client.write_registers(52, 1, unit=unit)
reply = client.write_registers(53, 1, unit=unit)
reply = client.write_registers(5, 2020, unit=unit) #2020 - Total managment
request = client.read_holding_registers(51, 1, unit=unit)
result1 = request.registers
print(result1)
reply = client.write_registers(52, 2, unit=unit)
reply = client.write_registers(53, 1, unit=unit)
reply = client.write_registers(5, 2020, unit=unit) #2020 - Total managment
request = client.read_holding_registers(51, 1, unit=unit)
result2 = request.registers
print(result2)
reply = client.write_registers(52, 3, unit=unit)
reply = client.write_registers(53, 1, unit=unit)
reply = client.write_registers(5, 2020, unit=unit) #2020 - Total managment
request = client.read_holding_registers(51, 1, unit=unit)
result3= request.registers
print(result3)
reply = client.write_registers(52, 1, unit=unit)
reply = client.write_registers(53, 1, unit=unit)
reply = client.write_registers(5, 2020, unit=unit) #2020 - Total managment
request = client.read_holding_registers(51, 1, unit=unit)
result4 = request.registers
print(result4)
reply = client.write_registers(52, 2, unit=unit)
reply = client.write_registers(53, 1, unit=unit)
reply = client.write_registers(5, 2020, unit=unit) #2020 - Total managment
request = client.read_holding_registers(51, 1, unit=unit)
result5 = request.registers
print(result5)
reply = client.write_registers(52, 3, unit=unit)
reply = client.write_registers(53, 1, unit=unit)
reply = client.write_registers(5, 2020, unit=unit) #2020 - Total managment
request = client.read_holding_registers(51, 1, unit=unit)
result6= request.registers
print(result6)
if (result1 == result4 and result2 == result5 and result3 == result6):
written_as = result1[0] * 0.1, result2[0] * 0.1, result3[0] * 0.1
print(result1, result2, result3)
#---------Write DB--------------------
with connection:
cur = connection.cursor()
cur.execute("SELECT * FROM wl5 ORDER BY id DESC LIMIT 1")
rows = cur.fetchall()
for row in rows:
print("{0}".format(row[2]))
print("{0}".format(row[3]))
print("{0}".format(row[4]))
try:
a1 = float(result1[0] * 0.1)
b1 = float(row[2])
silos14 = b1 - a1 - bool(b1 > a1) * 6553.5
print ("Расход:"f'{silos14:.1f}')
a2 = float(result2[0] * 0.1)
b2 = float(row[3])
silos15 = b2 - a2 - bool(b2 > a2) * 6553.5
print ("Расход:"f'{silos15:.1f}')
a3 = float(result3[0] * 0.1)
b3 = float(row[4])
silos16 = b3 - a3 - bool(b3 > a3) * 6553.5
print ("Расход:"f'{silos16:.1f}')
except:
#---------write db result-----
with connection.cursor() as cursor:
# Create a new record
sql = "INSERT INTO `line5` (`date`, `silos14`, silos15, silos16) VALUES (%s, %s, %s, %s)"
today = datetime.datetime.today()
newHireDate = today.strftime("%Y-%m-%d-%H.%M")
cursor.execute(sql, (newHireDate, silos14, silos15, silos16))
#------Write db wl5-------
sql = "INSERT INTO `wl5` (`date`, `product1`, `product2`, `product3`) VALUES (%s, %s, %s, %s)"
today = datetime.datetime.today()
newHireDate = today.strftime("%Y-%m-%d-%H.%M")
cursor.execute(sql, (newHireDate, result1[0] * 0.1, result2[0] * 0.1,result3[0] * 0.1))
connection.commit()
breakQuote:Traceback (most recent call last):
File "/home/pokip/test.py", line 76, in <module>
print("{0}".format(row[2]))
KeyError: 2
RE: KeyError: 2 - deanhystad - Aug-16-2022
Your error message says that "row" is a dictionary and 2 is not a key in the dictionary. I would print "rows" to see what was returned.
To get where your program throws a key error means that you must have something in the database.
RE: KeyError: 2 - ibreeden - Aug-16-2022
Apparently "row" does not contain what you expect. So in such cases always add a print statement just before the line where the error occurs.
print(row)What does it show?
Furtheron it is good practice to mention the columns you want instead of "select * from ...". Now you choose all columns and only use row[2], row[3] and row[4]. I is better to specify the columns by name so you can be sure you can use row[0], row[1] and row[2]
RE: KeyError: 2 - stsxbel - Aug-16-2022
(Aug-16-2022, 05:17 PM)ibreeden Wrote: Apparently "row" does not contain what you expect. So in such cases always add a print statement just before the line where the error occurs.
print(row)What does it show?
Furtheron it is good practice to mention the columns you want instead of "select * from ...". Now you choose all columns and only use row[2], row[3] and row[4]. I is better to specify the columns by name so you can be sure you can use row[0], row[1] and row[2]
Quote:{'id': 1, ‘date’: ‘22.05.2022’, ‘product1’: Decimal('0.0'), ‘product2’: Decimal('3.0'), ‘product3’: Decimal('0.0')}
Traceback (most recent call last):
File “/home/pokip/test.py”, line 77, in <module>
print(“{0}”.format(row))
KeyError: 3
RE: KeyError: 2 - deanhystad - Aug-16-2022
According to your print row is a dictioany, not a list. You can use row["id"] or row["date"] or row["product1"]. You cannot do row[2] or row[3]. Maybe that should be row["product2"] and row["product3].
Why do you do this "print("{0}".format(row[2]))" when it does the exact same thing as "print(row[2])"?
RE: KeyError: 2 - stsxbel - Aug-16-2022
(Aug-16-2022, 05:48 PM)deanhystad Wrote: According to your print row is a dictioany, not a list. You can use row["id"] or row["date"] or row["product1"]. You cannot do row[2] or row[3]. Maybe that should be row["product2"] and row["product3].
Why do you do this "print("{0}".format(row[2]))" when it does the exact same thing as "print(row[2])"?
Traceback (most recent call last):
File "/home/pokip/test.py", line 76, in <module>
print(row[2])
KeyError: 2
RE: KeyError: 2 - stsxbel - Aug-16-2022
Thanks, figured it out. You need to use row["product1"]. But the problem remained in another :-( everything works as it should, only the result is not written to the database for some reason :-(
[15877] [2178] [15877] [34338] [2178] [15877] [34338] [2178] [15877] [34338] [2178] [15877] [34338] [2178] [15877] 0.0 3.0 0.0 load1:-3433.8 load2:-214.8 load3:-1587.7
RE: KeyError: 2 - deanhystad - Aug-16-2022
That would be because you never execute an code that tries to add items to the database. This only gets called if an exception is raised.
with connection.cursor() as cursor:
# Create a new record
sql = "INSERT INTO `line5` (`date`, `silos14`, silos15, silos16) VALUES (%s, %s, %s, %s)"
today = datetime.datetime.today()
newHireDate = today.strftime("%Y-%m-%d-%H.%M")
cursor.execute(sql, (newHireDate, silos14, silos15, silos16))
#------Write db wl5-------
sql = "INSERT INTO `wl5` (`date`, `product1`, `product2`, `product3`) VALUES (%s, %s, %s, %s)"
today = datetime.datetime.today()
newHireDate = today.strftime("%Y-%m-%d-%H.%M")
cursor.execute(sql, (newHireDate, result1[0] * 0.1, result2[0] * 0.1,result3[0] * 0.1))Get rid of the try/except and see what happens.
RE: KeyError: 2 - stsxbel - Aug-16-2022
oops. Thank you. Everything is working :-)