CCF_100
/
relational
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

Use new class name

master
Salvo 'LtWorf' Tomaselli 2018-01-21 16:55:48 +07:00
parent bcdf81cdcd
commit 9101cee7ab
No known key found for this signature in database
GPG Key ID: B3A7CF0C801886CF
1 changed files with 13 additions and 13 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

26
relational/relation.py
Unescape Escape View File

@ -1,5 +1,5 @@
# Relational # Relational
# Copyright (C) 2008-2017 Salvo "LtWorf" Tomaselli # Copyright (C) 2008-2018 Salvo "LtWorf" Tomaselli
# #
# Relational is free software: you can redistribute it and/or modify # Relational is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by # it under the terms of the GNU General Public License as published by
@ -114,7 +114,7 @@ class Relation (object):
It is not exactely related to relational algebra. Just a method used It is not exactely related to relational algebra. Just a method used
internally. internally.
Will raise an exception if they don't share the same attributes''' Will raise an exception if they don't share the same attributes'''
if not isinstance(other, relation): if not isinstance(other, Relation):
raise TypeError('Expected an instance of the same class') raise TypeError('Expected an instance of the same class')
elif self.header == other.header: elif self.header == other.header:
return other return other
@ -128,7 +128,7 @@ class Relation (object):
''' '''
Selection, expr must be a valid Python expression; can contain field names. Selection, expr must be a valid Python expression; can contain field names.
''' '''
newt = relation() newt = Relation()
newt.header = Header(self.header) newt.header = Header(self.header)
try: try:
@ -155,13 +155,13 @@ class Relation (object):
Cartesian product. Attributes of the relations must differ. Cartesian product. Attributes of the relations must differ.
''' '''
if (not isinstance(other, relation)): if (not isinstance(other, Relation)):
raise Exception('Operand must be a relation') raise Exception('Operand must be a relation')
if self.header.sharedAttributes(other.header) != 0: if self.header.sharedAttributes(other.header) != 0:
raise Exception( raise Exception(
'Unable to perform product on relations with colliding attributes' 'Unable to perform product on relations with colliding attributes'
) )
newt = relation() newt = Relation()
newt.header = Header(self.header + other.header) newt.header = Header(self.header + other.header)
for i in self.content: for i in self.content:
@ -189,7 +189,7 @@ class Relation (object):
if len(ids) == 0: if len(ids) == 0:
raise Exception('Invalid attributes for projection') raise Exception('Invalid attributes for projection')
newt = relation() newt = Relation()
# Create the header # Create the header
h = (self.header[i] for i in ids) h = (self.header[i] for i in ids)
newt.header = Header(h) newt.header = Header(h)
@ -209,7 +209,7 @@ class Relation (object):
For example if you want to rename a to b, call For example if you want to rename a to b, call
rel.rename({'a':'b'}) rel.rename({'a':'b'})
''' '''
newt = relation() newt = Relation()
newt.header = self.header.rename(params) newt.header = self.header.rename(params)
newt.content = self.content newt.content = self.content
@ -223,7 +223,7 @@ class Relation (object):
Will return an empty one if there are no common items. Will return an empty one if there are no common items.
''' '''
other = self._rearrange(other) # Rearranges attributes' order other = self._rearrange(other) # Rearranges attributes' order
newt = relation() newt = Relation()
newt.header = Header(self.header) newt.header = Header(self.header)
newt.content = self.content.intersection(other.content) newt.content = self.content.intersection(other.content)
@ -234,7 +234,7 @@ class Relation (object):
operand but not in second one. operand but not in second one.
''' '''
other = self._rearrange(other) # Rearranges attributes' order other = self._rearrange(other) # Rearranges attributes' order
newt = relation() newt = Relation()
newt.header = Header(self.header) newt.header = Header(self.header)
newt.content = self.content.difference(other.content) newt.content = self.content.difference(other.content)
@ -271,7 +271,7 @@ class Relation (object):
and second operands. and second operands.
''' '''
other = self._rearrange(other) # Rearranges attributes' order other = self._rearrange(other) # Rearranges attributes' order
newt = relation() newt = Relation()
newt.header = Header(self.header) newt.header = Header(self.header)
newt.content = self.content.union(other.content) newt.content = self.content.union(other.content)
@ -305,7 +305,7 @@ class Relation (object):
shared = self.header.intersection(other.header) shared = self.header.intersection(other.header)
newt = relation() # Creates the new relation newt = Relation() # Creates the new relation
# Creating the header with all the fields, done like that because order is # Creating the header with all the fields, done like that because order is
# needed # needed
h = (i for i in other.header if i not in shared) h = (i for i in other.header if i not in shared)
@ -348,7 +348,7 @@ class Relation (object):
# List of attributes in common between the relations # List of attributes in common between the relations
shared = self.header.intersection(other.header) shared = self.header.intersection(other.header)
newt = relation() # Creates the new relation newt = Relation() # Creates the new relation
# Creating the header with all the fields, done like that because order is # Creating the header with all the fields, done like that because order is
# needed # needed
@ -376,7 +376,7 @@ class Relation (object):
return newt return newt
def __eq__(self, other): def __eq__(self, other):
if not isinstance(other, relation): if not isinstance(other, Relation):
return False return False
if len(self.content) != len(other.content): if len(self.content) != len(other.content):