Saving a string into a sqlite table, retrieving it again and comparing it to the original requires some filters to work and i dont know why exactly.
tl;dr
How can i retrieve string Data from the SQLITE DB without requiring Filter Nr 3 as its dangerous for more complex strings ?
import sqlite3
RAWSTRING = 'This is a DB Teststing'
# create database and table
currentdb = sqlite3.connect('test.db')
currentdb.execute('''CREATE TABLE tickertable (teststring text)''')
# enter RAWSTRING into databasse
currentdb.execute('''INSERT INTO tickertable VALUES(?);''', (RAWSTRING,))
# get RAWSTRING from database
cursorObj = currentdb.cursor()
cursorObj.execute('SELECT * FROM tickertable')
DB_RAWSTRING = cursorObj.fetchall()
currentdb.commit()
currentdb.close()
# Prints This is a DB Teststing
print('originalstring : ', RAWSTRING)
# Prints [('This is a DB Teststing',)]
print('retrieved from DB: ', DB_RAWSTRING)
# Get first entry from List because fetchall gives a list
FILTER1_DB_RAWSTRING = DB_RAWSTRING[0]
# Convert the Listelement to String because its still a listelement and comparing fails to string
FILTER2_DB_RAWSTRING = str(FILTER1_DB_RAWSTRING)
# Remove annoying db extra characters and i dont know why they exist anyway
FILTER3_DB_RAWSTRING = FILTER2_DB_RAWSTRING.replace("'", "").replace("(", "").replace(")", "").replace(",", "")
if RAWSTRING == FILTER3_DB_RAWSTRING:
print('Strings are the same as they should')
else:
print('String are not the same because of db weirdness')
So here's your problem: fetchall returns a list of tuples. This means that casting them to a string puts pesky parenthesis around each row and commas between each element of each row. If you'd like to retrieve the raw information from each column, that can be done by indexing the tuples:
entries = cursorObj.fetchall()
first_row = entries[0]
first_item = first_row[0]
print(first_item)
This ought to print just the content of the first row and column in the DB. If not, let me know!
David
I have data that looks like this:
minterms = [['1,x,x,x,x,x,x,x,x,x,x,x,x,x,x,x,x,x,x,x,x,x,x'], ['x,x,x,x,1,x,x,x,x,x,x,x,x,x,x,x,1,x,x,x,x,x,x']]
and I want to remove the single quotes around each array to get this:
minterms = [[1,x,x,x,x,x,x,x,x,x,x,x,x,x,x,x,x,x,x,x,x,x,x], [x,x,x,x,1,x,x,x,x,x,x,x,x,x,x,x,1,x,x,x,x,x,x]]
I have tried
mintermNew = minterms.replace("'", "")
and this doesn't work.
What am I doing wrong here?
Edit:
Here is a snippet of my code giving a bit more context.
dontcares = []
mintermAry = []
for mindata in minterms:
for mindataIdx in mindata:
mintermAry.append(mindataIdx.split())
print(SOPform(fullsymlst, mintermAry, dontcares))
return
I am using mindataIdx.split() to put the data into an array. MindataIdx is the data that looks like [['1,x,x,x,x....'].
Using .split("") as mentioned in the commends throws this error:
mintermAry.append(mindataIdx.split(""))
ValueError: empty separator
using .split(" ") yields no changes.
Edit 2:
The data is being read into a dataframe from a file. The first 4 rows I want to discard. I am using this method to do it.
df = df.replace('-', 'x', regex=True)
dfstr =
df.to_string(header=False,index=False,index_names=False).split('\n')
dfArray = np.array(dfstr)
dfArrayDel = np.delete(dfArray,range(4), 0)
dfArrayData = np.char.lstrip(dfArrayDel)
splitData = np.char.split(dfArrayData)
First of all, you're definitly doing somthing very wrong, as, there is no reason for there to be single quotes around the contents of an array. Is this a string you're working with? Please elaborate.
Ill have to assume you want to split the string in the array up into separate elements by the commas, in which case you would want this -
miniterms.map(s => s[0].split(","));
I can't tell if your writing in python or js, regardless your problem is that your 2d array contains only a single String, hence why it's all wrapped in quotes. If the String in your inner arrays were split into individual elements they would look like this:
[[1,'x','x','x','x','x','x','x','x','x','x','x'...], ['x','x','x','x',1,'x'...]]
1 is a Number and therefore not wrapped in quotes while x is a char or String and therefore is wrapped in quotes. These quotes are there only to visualize the variable datatype and are not part of the variable value itself. As the quotes don't exist they can't be removed (eg by using replace)
If your String, before putting it in an array looks like this.
data = '1,x,x,x,x,x,x,x,x,x,x,x'
You can split it into an array like this:
data_array = data.split("")
I needed to split mindataIdx by the comma to create individual items, and then it was able to be recognized by SOPform. Thanks!
dontcares = []
mintermAry = []
for mindata in minterms:
for mindataIdx in mindata:
mintermAry.append(mindataIdx.split(","))
print(SOPform(fullsymlst, mintermAry, dontcares))
I am trying to write user data from a file into a series of insert statements. I feel I am close but just missing one or two things. I am attempting to run a .format, but all I end up with are ?'s
import time, json, sqlite3
def insertsfromfile(file):
results = open(file).readlines()
output = open('UserINSERTFile.txt', 'w')
for rows in results:
jsonobject = json.loads(rows)
userid = jsonobject['user']['id']
name = jsonobject['user']['name']
screenname = jsonobject['user']['screen_name']
description = jsonobject['user']['description']
friendscount = jsonobject['user']['friends_count']
insert = ('INSERT INTO Users VALUES (?,?,?,?,?'.format(userid, name, screenname,description, friendscount)
insert = insert[:-1] + ''
output.write(insert)
output.close()
Thanks
I figured it out after reviewing it. Essentially I was missing that I had to combine the attributes together with my Insert string with the '+'. Also had to convert the variables to str() in case they were int.
This is my first go at using JSON in Python.
For example, say that I had a JSON file that lists employees first and last names.
How would I go about listing the first names of all the employees?
I can get it to display the first name for one person:
import json
json_data = open('app.json')
data = json.load(json_data)
print data['employees'][0]['firstname']
So I then tried two ways to list all the first names, both error:
print data['employees']['firstname']
print data['employees'][0:]['firstname']
You can use a list comprehension to extract all the first names:
print [emp['firstname'] for emp in data['employees']]
or use an explicit loop, printing each name separately:
for emp in data['employees']:
print emp['firstname']
I am running a server with cherrypy and python script. Currently, there is a web page containing data of a list of people, which i need to get. The format of the web page is as follow:
www.url1.com, firstName_1, lastName_1
www.url2.com, firstName_2, lastName_2
www.url3.com, firstName_3, lastName_3
I wish to display the list of names on my own webpage, with each name hyperlinked to their corresponding website.
I have read the webpage into a list with the following method:
#cherrypy.expose
def receiveData(self):
""" Get a list, one per line, of currently known online addresses,
separated by commas.
"""
method = "whoonline"
fptr = urllib2.urlopen("%s/%s" % (masterServer, method))
data = fptr.readlines()
fptr.close()
return data
But I don't know how to break the list into a list of lists at where the comma are. The result should give each smaller list three elements; URL, First Name, and Last Name. So I was wondering if anyone could help.
Thank you in advance!
You can iterate over fptr, no need to call readlines()
data = [line.split(', ') for line in fptr]
You need the split(',') method on each string:
data = [ line.split(',') for line in fptr.readlines() ]
lists = []
for line in data:
lists.append([x.strip() for x in line.split(',')])
If you data is a big 'ole string (potentially with leading or trailing spaces), do it this way:
lines=""" www.url1.com, firstName_1, lastName_1
www.url2.com, firstName_2 , lastName_2
www.url3.com, firstName_3, lastName_3 """
data=[]
for line in lines.split('\n'):
t=[e.strip() for e in line.split(',')]
data.append(t)
print data
Out:
[['www.url1.com', 'firstName_1', 'lastName_1'], ['www.url2.com', 'firstName_2',
'lastName_2'], ['www.url3.com', 'firstName_3', 'lastName_3']]
Notice the leading and trailing spaces are removed.