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Python‎ > ‎keywords‎ > ‎

Definition

Keyword assert value, module from sources.

Syntax

from

Parameters

None

Examples

Here in this example, the CharField is used to store the data into the field. The data is recorded and saved in models.py and retrieved and displayed through the views.py.

Steps for creating virtual environment, startproject, startapp, creating database, and migrating the data, and running server to check the app.

virtualenenv djangoschool
cd djangoschool
.\Scripts\activate
pip install django
python .\Scripts\django-admin.py startproject mysite
python manage.py migrate
python manage.py startapp dbapp
python manage.py makemigrations dbapp

mysite/settings,py

INSTALLED_APPS = (

'django.contrib.admin',

'django.contrib.auth',

'django.contrib.contenttypes',

'django.contrib.sessions',

'django.contrib.messages',

'django.contrib.staticfiles','dbapp',

)

mysite/urls.py

from django.conf.urls import include, url

from dbapp.views import Display

urlpatterns = [

url(r'^', Display),

]

dbapp/models.py

from django.db import models

class LongLife(models.Model):

groups=(('male','0-40'),('female','0-40'))

genderfield=models.CharField(max_length=50,choices=groups)

v=LongLife(genderfield="Casey")

v.save()

dbapp/views.py

from django.http import HttpResponse

from . models import LongLife

def Display (request):

return HttpResponse(LongLife.objects.filter(genderfield="Casey").values())

Here, this examples, mydb.db database is created and in that database Table3 is created with Fields, name, email, telephone and income. The values are displayed through for loop by order of income in html file.

Steps for creating virtual environment, startproject, startapp, creating database, and migrating the data, and running server to check the app.

virtualenenv pythonlake
cd pythonlake
.\Scripts\activate
pip install django
python .\Scripts\django-admin.py startproject mysite
python manage.py migrate
python manage.py startapp mydb
python manage.py makemigrations mydb

mysite/settings.py

INSTALLED_APPS = (

'django.contrib.admin',

'django.contrib.auth',

'django.contrib.contenttypes',

'django.contrib.sessions',

'django.contrib.messages',

'django.contrib.staticfiles','mydb',

)

mysite/urls.py

from django.conf.urls import url

from mydb.views import DataBase

urlpatterns = [

url(r'^$', DataBase),

]

mydb/views.py

from django.shortcuts import render

import sqlite3

def DataBase (request):

conn=sqlite3.connect('mydb.db')

cursor=conn.cursor()

cursor.execute('''CREATE TABLE table3(name text, phone text, email text, income text)''')

cursor.execute('''INSERT INTO table3 VALUES(' Erica ', ' 571 402 2992 ', ' erica.steve@ibm.com ', ' 180000 ')''')

cursor.execute('''INSERT INTO table3 VALUES(' Strube ', ' 571 402 2212 ', ' marya_strube@care.com ', ' 890000 ')''')

conn.commit()

for row in cursor.execute('SELECT * FROM table3 ORDER BY income'):

response=row

return render(request, 'mydb\index.html', {'response':response} )

mydb/index.html

<!DOCTYPE html>

<html>

<title>Table3</title>

</head>

<body>

</body>

</html>

The django web framework returns with hyperlink created through html5 integrated with django Scripts.

Steps for creating virtual environment, startproject, startapps, migration, & running server:

virtualenv string
cd string
.\Scripts\activate
pip install django
python .\Scripts\django-admin.py startproject str
cd str
python manage.py runserver
key ctr c to break the server
python manage.py startapp htmlapp
python manage.py runserver

File structure

settings.py

INSTALLED_APPS = (

'django.contrib.admin',

'django.contrib.auth',

'django.contrib.contenttypes',

'django.contrib.sessions',

'django.contrib.messages',

'django.contrib.staticfiles','htmlapp',

)

urls.py

from django.conf.urls import url, patterns

from htmlapp.views import html_links

urlpatterns = patterns('',

url(r'^html_links/', html_links),

)

httpapp/views.py

from django.http import HttpResponse

def html_links(request):

link='<div style="background-color:pink; color:white; padding:20px;">'\

'<a href="http://www.pythonlake.com/">Python Lake</a> <hr>' \

'<a href="http://www.pythonlake.com/python/django">Django</a> <hr> ' \

'<a href="http://www.pythonlake.com/python/django/djangohttp">django.http</a> <hr> ' \

'<a href="http://www.pythonlake.com/python/django/djangohttp/httpresponse">HttpResponse</a> <hr> ' \

'</div>'

return HttpResponse(link)

Running the server through Window CMD command.

The django web framework is used to create the application which convert the string into uppercase using str.upper method. The string_method_upper.py calls the string_method.views.py file to render the function.

Windows CMD commands for creating virtualenv, startproject, startapp, and running server.

virtualenv string
cd string
.\Scripts\activate
pip install django
python .\Scripts\django-admin.py startproject str
cd str
python manage.py runserver
python manage.py startapp string_methods
python manage.py startapp string_method_upper
python manage.py runserver

string_method_upper/views.py

from string_methods.views import string_upper

def string_method_upper (request):

return string_upper(request)

string_methods/views.py

from django.http import HttpResponse

def string_upper(request):

return HttpResponse("Python is a simple, powerful and high-level programming language "

"and the logic and structure is consistent with the way we "

"reasons. ".upper())

urls.py

from django.conf.urls import include, url, patterns

from string_methods.views import*

from string_method_upper.views import *

urlpatterns=patterns('', url(r'^string_method_upper/', string_method_upper),)

settings.py

INSTALLED_APPS = (

'django.contrib.admin',

'django.contrib.auth',

'django.contrib.contenttypes',

'django.contrib.sessions',

'django.contrib.messages',

'django.contrib.staticfiles','string_methods', 'string_method_upper',

)

The equal to:

from fractions import Fraction
a=Fraction(5,16)
b=Fraction(9,16)
c=a+b
print(c)

>>>
7/8
>>>

The returns are:

>>> from fractions import Fraction
>>> a=Fractions(1,3)
>>> a=Fraction(1,4)
>>> b=Fraction(3,4)
>>> a+b
Fraction(1, 1)
>>> a-b
Fraction(-1, 2)
>>> c=Fraction(1,4)
>>> c+a
Fraction(1, 2)
>>>

The method computed the int(value) of the decimal and then run loop through range() function.

from decimal import Decimal

a=int(Decimal(1.1).log10()+Decimal(1.233).logb()- Decimal(1.1).log10()%Decimal(.49).sqrt())

for i in range(a,10):

print(i)

print(i/Decimal(1.1).log10())

>>>

0
0E+29
1
24.15885792809678504023429545
2
48.31771585619357008046859090
3
72.47657378429035512070288634
4
96.63543171238714016093718179
5
120.7942896404839252011714772
6
144.9531475685807102414057727
7
169.1120054966774952816400681
8
193.2708634247742803218743636
9
217.4297213528710653621086590
>>>

from decimal import Decimal

The method test the equality tow Decimal equations.

from decimal import Decimal

x=(Decimal(1).logical_and(Decimal(1))).__sub__(Decimal(0).logical_and(Decimal(1)))
y=(Decimal(1).logical_and(Decimal(1))).__mul__(Decimal(0).logical_and(Decimal(1)))
print(x.__eq__(y))

>>>
False
>>>

from decimal import Decimal

The method return with the difference in the set items:

from decimal import Decimal

set1={Decimal(0.1).to_integral_value(),Decimal(1.9).to_integral_exact(),Decimal(1.5000001).to_integral(), Decimal(10).shift(2)}
set2={ Decimal(1).scaleb(0), Decimal(1).remainder_near(2),Decimal(1.0000).normalize()}

print(set1.copy())

>>>

{Decimal('1000'), Decimal('0'), Decimal('2')}

>>>

The tkinter.Entry is used to check the string characteristics through string methods.

from tkinter import*

master=Tk()
master.title("String methods")

def cap():
  try:
c=str.capitalize(s.get())
s.set(c)

  except ValueError:
  pass

def cfold():
try:
c=str.casefold(s.get())
s.set(c)

except ValueError:
pass

def ifier():
try:
if str.isidentifier(s.get())==True:
s.set("Yes")

else:
s.set("No")

except ValueError:
pass

def ipace():
try:
if str.isspace(s.get())==True:
s.set("Yes")

else:
s.set("No")

except ValueError:
pass

def iric():
try:
if str.isnumeric(s.get())==True:
s.set("Yes")
else:
s.set("No")

except ValueError:
pass

def ower():
try:
if str.islower(s.get())==True:
s.set("Yes")

else:
s.set("No")

except ValueError:
pass

def inum():
try:
if str.isalnum(s.get())==True:
s.set("Yes")

else:
s.set("No")
except ValueError:
pass

def imal():
try:
if str.isdecimal(s.get())==True:
s.set("Yes")

else:
s.set("No")

except ValueError:
pass



def igit():
try:
if str.isdigit(s.get())==True:
s.set("Yes")

else:
s.set("No")

except ValueError:
pass

def clr():
try:
s.set("")


except ValueError:
pass

s = StringVar()

entry=Entry(master, textvariable=s)
entry.grid(row=0, columnspan=4, sticky=W+E)

button_capitalize=Button(master, text="capitalize", width=10, command=cap)
button_capitalize.grid(row=2, column=0)

button_casefold=Button(master, text="casefold",width=10, command=cfold)
button_casefold.grid(row=2, column=1)

button_isidentifier=Button(master, text="isidentifier",width=10,command=ifier)
button_isidentifier.grid(row=2, column=2)

button_isspace=Button(master, text="isspace",width=10, command=ipace)
button_isspace.grid(row=3, column=0)

button_endswith=Button(master, text="endswith", width=10, command=iric)
button_endswith.grid(row=3, column=1)

button_islower=Button(master, text="islower",width=10, command=ower)
button_islower.grid(row=3, column=2)

button_isalnum=Button(master, text="isalnum",width=10, command=inum)
button_isalnum.grid(row=4, column=0)

button_isdecimal=Button(master, text="isdecimal",width=10, command=imal)
button_isdecimal.grid(row=4, column=1)

button_isdigit=Button(master, text="isdigit",width=10, command=igit)
button_isdigit.grid(row=4, column=2)

button_clear=Button(master, text="Clear", command=clr )
button_clear.grid(row=5, columnspan=3,sticky=W+E)

Keywords

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