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Why can't this python code not be executed?

As soon as I run this python code that includes some mysql, all I get are the three greater or less signs(>>>). Any help would be much appreciated!
My code consists of trying to obtain temperatures through a ds18b20 connected to my raspberry pi 3 and sending that data into a mysql database that I have created.
Here is the python/mysql code :
import os
import glob
import time
import MySQLdb
import datetime
i = datetime.datetime.now()
db = MySQLdb.connect(host = "127.0.0.1", user = "root", passwd = "test", db = "temp_pi")
cur = db.cursor()
os.system('modprobe w1-gpio')
os.system('modprobe w1-therm')
base_dir = '/sys/bus/w1/devices/'
device_folder = glob.glob(base_dir + '28*')[0]
device_file = device_folder + '/w1_slave'
def read_temp_raw():
f = open(device_file, 'r')
lines = f.readlines()
f.close()
return lines
def read_temp():
lines = read_temp_raw()
while lines[0].strip()[-3:] != 'YES':
time.sleep(0.2)
lines = read_temp_raw()
equals_pos = lines[1].find('t=')
if equals_pos != -1:
temp_string = lines[1][equals_pos+2:]
temp_c = float(temp_string) / 1000.0
temp_f = temp_c * 9.0 / 5.0 + 32.0
return temp_c
while True:
print ("recording data into database(period = 5s.)....press ctrl+Z to stop!")
valT = str(read_temp())
year = str(i.year)
month = str(i.month)
day = str(i.day)
date = day + "-" + month + "-" + year
hour = str(i.hour)
minute = str(i.minute)
second = str(i.second)
timestr = hour + ":" + minute + ":" + second
try:
cur.execute("""INSERT INTO TAB_CLASSROOM(temp_c,T_Date,T_Time) VALUES(%s,%s,%s)""",(valT,date,time))
db.commit()
except:
db.rollback()
time.sleep(10)
cur.close()
db.close()

You've never run anything inside that code. The bulk of your code is inside read_temp() and it isn't called anywhere in it. The >>> means the program has ended and it's entered interpreter mode. Add some code after it for it to work the way you want it to.

You are not, in fact running anything. Assuming you do
python myscript.py
python will load the file and run it - which means execute the code line-by-line. You will find that the first few lines outside of functions are simply executed. Then you define some functions, but never call them.
You should probably add
read_temp()
at the end of the script.

Error ------ unexpected EOF while parsing

I am running this code on Python 3(IDLE) on my raspberry pi 3 whith the latest raspbian software. With this code I am trying to obtain temperature data through ds18b20 sensor and sending that same data towards the mysql database I created.
From the try: to the end of the if connection.is_connected(), I am establishing the connection to the mysql database.
From the if os.system('modprobe w1-gpio') to return temp_c, I am obtaining the temperature data through the ds18b20 sensor.
From the Whiletrue to the end of my code, I try to send the temperature data into a specific table intitled TAB_CLASSROOM.
Help would be very much appreciated!
HERE IS THE FULL ERROR!:
Traceback (most recent call last):
File "/home/pi/Desktop/mysqlfinal1test.py", line 74
db.close()
^
SyntaxError: unexpected EOF while parsing
Here is the python including mysql code :
import os
import glob
import time
import MySQLdb
import datetime
import mysql.connector
from mysql.connector import Error
i = datetime.datetime.now()
try:
connection = mysql.connector.connect(host='127.0.0.1',
database='temp_pi',
user='root',
password='test')
if connection.is_connected():
db_Info = connection.get_server_info()
print("Connected to MySQL database... MySQL Server version on ",db_Info)
cursor = connection.cursor()
cursor.execute("select database();")
record = cursor.fetchone()
print ("Your connected to - ", record)
os.system('modprobe w1-gpio')
os.system('modprobe w1-therm')
base_dir = '/sys/bus/w1/devices/'
device_folder = glob.glob(base_dir + '28*')[0]
device_file = device_folder + '/w1_slave'
def read_temp_raw():
f = open(device_file, 'r')
lines = f.readlines()
f.close()
return lines
def read_temp():
lines = read_temp_raw()
while lines[0].strip()[-3:] != 'YES':
time.sleep(0.2)
lines = read_temp_raw()
equals_pos = lines[1].find('t=')
if equals_pos != -1:
temp_string = lines[1][equals_pos+2:]
temp_c = float(temp_string) / 1000.0
temp_f = temp_c * 9.0 / 5.0 + 32.0
return temp_c
while True:
print("recording data into database(period = 5s.)....press ctrl+Z to stop!")
valT = str(read_temp())
year = str(i.year)
month = str(i.month)
day = str(i.day)
date = day + "-" + month + "-" + year
hour = str(i.hour)
minute = str(i.minute)
second = str(i.second)
timestr = hour + ":" + minute + ":" + second
try:
cur.execute("""INSERT INTO TAB_CLASSROOM(temp_c,T_Date,T_Time) VALUES(%s,%s,%s)""",(valT,date,time))
db.commit()
except:
db.rollback()
time.sleep(10)
cur.close()
db.close()

Most of posted program is a huge try block with no except clause. Thus, when the parser hits the bottom of the file, it has no way to finish off the open control block.
The try is at line 11; we run out of input after line 74, without any except for that try.
I suspect that your indentation is faulty (among other things), since this try includes two function definitions. Still, you have two try statements, and only the one except.

Using Return round(function,1) giving syntax error

Why python give Sytanx error ''RETURN OUTSIDE FUNCTION''
Error line 35 :>>>> return round(temp_c,1) ? I'm beginner programmer and i want to store my sensor data mysql . As you see my return round(temp_c,1) in my function and if statement.
Here is my full code
import os
import time
import datetime
import glob
import mysql.connector
from mysql.connector import errorcode
from time import strftime
os.system('modprobe w1-gpio')
os.system('modprobe w1-therm')
temp_sensor = '/sys/bus/w1/devices/28-000008a43c0e/w1_slave'
#Connect MySQL
#-----------------------------------------------------------------------------------
cnx = mysql.connector.connect(user='root',password='invoker',
host='localhost',
database='temp-at-interrupt')
cnx.close()
#
#Get Temperature Values.
#-----------------------------------------------------------------------------------
def tempRead():
t = open(temp_sensor, 'r')
lines = t.readlines()
t.close()
temp_output = lines[1].find('t=')
if temp_output != -1:
temp_string = lines[1].strip()[temp_output+2:]
temp_c = float(temp_string)/1000.0
return round(temp_c,1)
#Insert new data
#-----------------------------------------------------------------------------------
while True:
print(temp)
datatimeWrite = (time.strftime("%Y-%m-%d ") + time.strftime("%H:%M:%S"))
print (datetimeWrite)
sql = ("""INSERT INTO tempLog (datetime,temperature) VALUES (%s,%s)""",(datetimeWrite,temp))
try:
print ("Writing to database...")
# Execute the SQL command
cur.execute(*sql)
# Commit your changes in the database
db.commit()
print ("Write Complete")
except:
# Rollback in case there is any error
db.rollback()
print ("Failed writing to database")
cur.close()
db.close()
break

You use return not inside a function, which is illegal Python (and most programming languages) syntax.
if temp_output != -1:
temp_string = lines[1].strip()[temp_output+2:]
temp_c = float(temp_string)/1000.0
return round(temp_c,1) # <---- problematic return statement outside a function
I believe that this if block is part of tempRead() function, so a fix is to delete the empty line before the if block, and ident all the code in the if block by 4 spaces:
def tempRead():
t = open(temp_sensor, 'r')
lines = t.readlines()
t.close()
temp_output = lines[1].find('t=')
if temp_output != -1:
temp_string = lines[1].strip()[temp_output+2:]
temp_c = float(temp_string)/1000.0
return round(temp_c,1)

Python for loop dropping after 1 iteration

I am new to python and thought I would practice what I have been learning to complete a little task. Essentially I am inserting a cognimatic cameras data into a database from a .csv file that I pulled from the web. sadly I have had to omit all the connection details as it can only be accessed from my works computer which means the script cannot be run.
To the problem!
I have a for loop that iterates through the cameras in the system, running this script:
#!/usr/bin/python
import pymssql
import urllib2
import sys
import getpass
import csv
import os
attempts = 0 #connection attempt counter
#check db connection with tsql -H cabernet.ad.uow.edu.au -p 1433 -U ADUOW\\mbeavis -P mb1987 -D library_gate_counts
server = "*****" #sever address
#myUser = 'ADUOW\\' + raw_input("User: ")# User and password for server. Will this be needed when the script runs on the server? # Ask David
#passw = getpass.getpass("Password: ")
while attempts < 3: # attempt to connect 3 times
try: #try connection
conn = pymssql.connect(server = server, user = '****', password = '****', database = "***", port='1433',timeout = 15, login_timeout = 15)
break
except pymssql.Error as e: #if connection fails print error information
attempts += 1
print type(e)
print e.args
camCursor = conn.cursor() #creates a cursor on the database
camCursor.execute("SELECT * FROM dbo.CAMERAS") #Selects the camera names and connection details
for rows in camCursor:
print rows
Everything is fine and the loop runs as it should, however when I actually try and do anything with the data the loop runs once and ends, this is the full script:
#!/usr/bin/python
import pymssql
import urllib2
import sys
import getpass
import csv
import os
attempts = 0 #connection attempt counter
#check db connection with tsql -H cabernet.ad.uow.edu.au -p 1433 -U ADUOW\\mbeavis -P mb1987 -D library_gate_counts
server = "*****" #sever address
#myUser = 'ADUOW\\' + raw_input("User: ")# User and password for server. Will this be needed when the script runs on the server? # Ask David
#passw = getpass.getpass("Password: ")
while attempts < 3: # attempt to connect 3 times
try: #try connection
conn = pymssql.connect(server = server, user = '****', password = '****', database = "***", port='1433',timeout = 15, login_timeout = 15)
break
except pymssql.Error as e: #if connection fails print error information
attempts += 1
print type(e)
print e.args
camCursor = conn.cursor() #creates a cursor on the database
camCursor.execute("SELECT * FROM dbo.CAMERAS") #Selects the camera names and connection details
for rows in camCursor:
print rows
cameraName = str(rows[0]) #converts UNICODE camera name to string
connectionDetails = str(rows[1]) #converts UNICODE connection details to string
try: #try connection
#connect to webpage, this will be changed to loop through the entire range of cameras, which will
#have their names and connection details stored in a seperate database table
prefix = "***"
suffix = "**suffix"
response = urllib2.urlopen(prefix + connectionDetails + suffix, timeout = 5)
content = response.read() #read the data for the csv page into content
f = open( "/tmp/test.csv", 'w' ) #open a file for writing (test phase only)
f.write( content ) #write the data stored in content to file
f.close() #close file
print content #prints out content
with open( "/tmp/test.csv", 'rb' ) as csvFile: #opens the .csv file previously created
reader = csv.DictReader(csvFile) #reader object of DictReader, allows for the first row to be the dictionary keys for the following rows
for row in reader: #loop through each row
start = row['Interval start']
end = row['Interval stop']
camName = row['Counter name']
pplIn = int(row['Pedestrians coming in'])
pplOut = int(row['Pedestrians going out'])
insertCursor = conn.cursor()
insert = "INSERT INTO dbo.COUNTS VALUES (%s, %s, %d, %d)"
insertCursor.execute(insert, (camName, start, pplIn, pplOut))
conn.commit()
except urllib2.URLError as e: #catch URL errors
print type(e)
print e.args
except urllib2.HTTPError as e: #catch HTTP erros
print type(e)
print e.code
I have been scratching my head as I cannot see why there is a problem, but maybe I just need some fresh eyes on it. Any help would be great cheers!

Have you tried to do something like
queryResult = camCursor.execute("SELECT * FROM dbo.CAMERAS")
for rows in queryResult:
...
I guess this might solve the problem, which is probably the fact that you're trying to iterate over a cursor instead of the results.
You might find this way interesting as well:
camCursor.execute("SELECT * FROM dbo.CAMERAS")
for rows in camCursor.fetchall():
...
Source: https://docs.python.org/2/library/sqlite3.html

How to insert data from Python program to MySQL database at intervals

I have created a temperature sensor (using DS18B20 temperature sensor) and wrote the python program to read and display the temperature every 10 seconds. It worked fine. Later, I modified the code to save the recordings of each 10 sec to a MySQL database. Now, the problem is that it records AND uploads the data to the databse for the first time it reads. Then, I get an error message. So basically, the program reads and uploads to the database for once and then quits after the error.
Please tell me how to fix this!
Thanks a lot!
Here is the code:
import os
import time
import MySQLdb
import datetime
i = datetime.datetime.now()
db = MySQLdb.connect(host = "localhost", user = "root", passwd = "bb9125ap", db = "PY1")
cur = db.cursor()
os.system('modprobe w1-gpio')
os.system('modprobe w1-therm')
temp_sensor = '/sys/bus/w1/devices/28-00042d6745ff/w1_slave'
def temp_raw():
f = open(temp_sensor,'r')
lines = f.readlines()
f.close
return lines
def read_temp():
lines = temp_raw()
while lines[0].strip()[-3:] != 'YES':
time.sleep(0.2)
lines = temp_raw()
temp_output = lines[1].find('t=')
if temp_output != -1:
temp_string = lines[1].strip()[temp_output+2:]
temp_c = float(temp_string) / 1000.0
return temp_c
while True:
print "recording data into database(period = 5s.)....press ctrl+Z to stop!"
valT = str(read_temp())
year = str(i.year)
month = str(i.month)
day = str(i.day)
date = day + "-" + month + "-" + year
hour = str(i.hour)
minute = str(i.minute)
second = str(i.second)
time = hour + ":" + minute + ":" + second
try:
cur.execute("""INSERT INTO PY1.DUMP1(temp_c,rec_time,rec_date) VALUES(%s,%s,%s)""",(valT,time,date))
db.commit()
except:
db.rollback()
time.sleep(10)
cur.close()
db.close()
Program name is temp1.py and line 54 according to my editor is db.rollback()
Here is the error message I get
Traceback (most recent call last):
File "temp1.py" , line 54 , in time.sleep(10)
Attribute:'str' object has no attribute 'sleep'

You're overwriting your imported time with a local variable time, converting it to a string.
time = hour + ":" + minute + ":" + second