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Radix sort

0 likes • Nov 19, 2022
Python
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radians to degrees

CodeCatch
0 likes • Nov 19, 2022
Python
from math import pi
def rads_to_degrees(rad):
return (rad * 180.0) / pi
rads_to_degrees(pi / 2) # 90.0

Topological sort

CodeCatch
0 likes • Nov 19, 2022
Python
#Python program to print topological sorting of a DAG
from collections import defaultdict
#Class to represent a graph
class Graph:
def __init__(self,vertices):
self.graph = defaultdict(list) #dictionary containing adjacency List
self.V = vertices #No. of vertices
# function to add an edge to graph
def addEdge(self,u,v):
self.graph[u].append(v)
# A recursive function used by topologicalSort
def topologicalSortUtil(self,v,visited,stack):
# Mark the current node as visited.
visited[v] = True
# Recur for all the vertices adjacent to this vertex
for i in self.graph[v]:
if visited[i] == False:
self.topologicalSortUtil(i,visited,stack)
# Push current vertex to stack which stores result
stack.insert(0,v)
# The function to do Topological Sort. It uses recursive
# topologicalSortUtil()
def topologicalSort(self):
# Mark all the vertices as not visited
visited = [False]*self.V
stack =[]
# Call the recursive helper function to store Topological
# Sort starting from all vertices one by one
for i in range(self.V):
if visited[i] == False:
self.topologicalSortUtil(i,visited,stack)
# Print contents of stack
print(stack)
g= Graph(6)
g.addEdge(5, 2);
g.addEdge(5, 0);
g.addEdge(4, 0);
g.addEdge(4, 1);
g.addEdge(2, 3);
g.addEdge(3, 1);
print("Following is a Topological Sort of the given graph")
g.topologicalSort()

Using logic with sets

AustinLeath
0 likes • Nov 18, 2022
Python
#Sets
U = {0,1,2,3,4,5,6,7,8,9}
P = {1,2,3,4}
Q = {4,5,6}
R = {3,4,6,8,9}
def set2bits(xs,us) :
bs=[]
for x in us :
if x in xs :
bs.append(1)
else:
bs.append(0)
assert len(us) == len(bs)
return bs
def union(set1,set2) :
finalSet = set()
bitList1 = set2bits(set1, U)
bitList2 = set2bits(set2, U)
for i in range(len(U)) :
if(bitList1[i] or bitList2[i]) :
finalSet.add(i)
return finalSet
def intersection(set1,set2) :
finalSet = set()
bitList1 = set2bits(set1, U)
bitList2 = set2bits(set2, U)
for i in range(len(U)) :
if(bitList1[i] and bitList2[i]) :
finalSet.add(i)
return finalSet
def compliment(set1) :
finalSet = set()
bitList = set2bits(set1, U)
for i in range(len(U)) :
if(not bitList[i]) :
finalSet.add(i)
return finalSet
def implication(a,b):
return union(compliment(a), b)
###########################################################################################
###################### Problems 1-6 #######################################
###########################################################################################
#p \/ (q /\ r) = (p \/ q) /\ (p \/ r)
def prob1():
return union(P, intersection(Q,R)) == intersection(union(P,Q), union(P,R))
#p /\ (q \/ r) = (p /\ q) \/ (p /\ r)
def prob2():
return intersection(P, union(Q,R)) == union(intersection(P,Q), intersection(P,R))
#~(p /\ q) = ~p \/ ~q
def prob3():
return compliment(intersection(P,R)) == union(compliment(P), compliment(R))
#~(p \/ q) = ~p /\ ~q
def prob4():
return compliment(union(P,Q)) == intersection(compliment(P), compliment(Q))
#(p=>q) = (~q => ~p)
def prob5():
return implication(P,Q) == implication(compliment(Q), compliment(P))
#(p => q) /\ (q => r) => (p => r)
def prob6():
return implication(intersection(implication(P,Q), implication(Q,R)), implication(P,R))
print("Problem 1: ", prob1())
print("Problem 2: ", prob2())
print("Problem 3: ", prob3())
print("Problem 4: ", prob4())
print("Problem 5: ", prob5())
print("Problem 6: ", prob6())
'''
Problem 1: True
Problem 2: True
Problem 3: True
Problem 4: True
Problem 5: True
Problem 6: {0, 1, 2, 3, 4, 5, 6, 7, 8, 9}
'''

get LDAP user

AustinLeath
0 likes • Nov 18, 2022
Python
def get_ldap_user(member_cn, user, passwrd):
'''
Get an LDAP user and return the SAMAccountName
'''
#---- Setting up the Connection
#account used for binding - Avoid putting these in version control
bindDN = str(user) + "@unt.ad.unt.edu"
bindPass = passwrd
#set some tuneables for the LDAP library.
ldap.set_option(ldap.OPT_X_TLS_REQUIRE_CERT, ldap.OPT_X_TLS_ALLOW)
#ldap.set_option(ldap.OPT_X_TLS_CACERTFILE, CACERTFILE)
conn = ldap.initialize('ldaps://unt.ad.unt.edu')
conn.protocol_version = 3
conn.set_option(ldap.OPT_REFERRALS, 0)
#authenticate the connection so that you can make additional queries
try:
result = conn.simple_bind_s(bindDN, bindPass)
except ldap.INVALID_CREDENTIALS:
result = "Invalid credentials for %s" % user
sys.exit()
#build query in the form of (uid=user)
ldap_query = '(|(displayName=' + member_cn + ')(cn='+ member_cn + ')(name=' + member_cn + '))'
ldap_info = conn.search_s('DC=unt,DC=ad,DC=unt,DC=edu', ldap.SCOPE_SUBTREE, filterstr=ldap_query)
sAMAccountName = str(ldap_info[0][1]['sAMAccountName']).replace("[b'", "").replace("']","")
return sAMAccountName

Nodes and Trees

AustinLeath
0 likes • Nov 18, 2022
Python
import random
class Node:
def __init__(self, c):
self.left = None
self.right = None
self.color = c
def SetColor(self,c) :
self.color = c
def PrintNode(self) :
print(self.color)
def insert(s, root, i, n):
if i < n:
temp = Node(s[i])
root = temp
root.left = insert(s, root.left,2 * i + 1, n)
root.right = insert(s, root.right,2 * i + 2, n)
return root
def MakeTree(s) :
list = insert(s,None,0,len(s))
return list
def MakeSet() :
s = []
count = random.randint(7,12)
for _ in range(count) :
color = random.randint(0,1) == 0 and "Red" or "White"
s.append(color)
return s
def ChangeColor(root) :
if (root != None) :
if (root.color == "White") :
root.SetColor("Red")
ChangeColor(root.left)
ChangeColor(root.right)
def PrintList(root) :
if root.left != None :
PrintList(root.left)
else :
root.PrintNode()
if root.right != None :
PrintList(root.right)
else :
root.PrintNode()
t1 = MakeTree(MakeSet())
print("Original Colors For Tree 1:\n")
PrintList(t1)
ChangeColor(t1)
print("New Colors For Tree 1:\n")
PrintList(t1)
t2 = MakeTree(MakeSet())
print("Original Colors For Tree 2:\n")
PrintList(t2)
ChangeColor(t2)
print("New Colors For Tree 2:\n")
PrintList(t2)
t3 = MakeTree(MakeSet())
print("Original Colors For Tree 3:\n")
PrintList(t3)
ChangeColor(t3)
print("New Colors For Tree 3:\n")
PrintList(t3)

when predicate lambda

CodeCatch
0 likes • Nov 19, 2022
Python
def when(predicate, when_true):
return lambda x: when_true(x) if predicate(x) else x
double_even_numbers = when(lambda x: x % 2 == 0, lambda x : x * 2)
print(double_even_numbers(2)) # 4
print(double_even_numbers(1)) # 1