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Topological sort

0 likes • Nov 19, 2022
Python
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Remove i'th character

CodeCatch
0 likes • Nov 19, 2022
Python
# Python code to demonstrate
# method to remove i'th character
# Naive Method
# Initializing String
test_str = "CodeCatch"
# Printing original string
print ("The original string is : " + test_str)
# Removing char at pos 3
# using loop
new_str = ""
for i in range(len(test_str)):
if i != 2:
new_str = new_str + test_str[i]
# Printing string after removal
print ("The string after removal of i'th character : " + new_str)

collect dictionary

CodeCatch
0 likes • Nov 19, 2022
Python
from collections import defaultdict
def collect_dictionary(obj):
inv_obj = defaultdict(list)
for key, value in obj.items():
inv_obj[value].append(key)
return dict(inv_obj)
ages = {
'Peter': 10,
'Isabel': 10,
'Anna': 9,
}
collect_dictionary(ages) # { 10: ['Peter', 'Isabel'], 9: ['Anna'] }

UNT CSCE 2100 Assignment 6

AustinLeath
0 likes • Nov 18, 2022
Python
"""
Assignment 6
The goal is to make a graph of
who bit who and who was bitten.
There should be 10 nodes and 15 edges.
3 arrows of biting each other and
3 arrows of someone biting themselves.
Networkx can not do self biting
arrows, but it is in the code.
"""
from graphviz import Digraph as DDotGraph
from graphviz import Graph as UDotGraph
import networkx as nx
from networkx.algorithms.dag import transitive_closure
import graphviz as gv
import matplotlib.pyplot as plt
import numpy as np
from numpy.linalg import matrix_power
"""
class DGraph:
def __init__(self):
self.d = dict()
def clear(self):
self.d = dict()
def add_node(self,n):
if not self.d.get(n):
self.d[n] = set()
def add_edge(self,e):
f,t=e
self.add_node(f)
self.add_node(t)
vs=self.d.get(f)
if not vs:
self.d[f] = {t}
else:
vs.add(t)
def add_edges_from(self,es):
for e in es:
self.add_edge(e)
def edges(self):
for f in self.d:
for t in self.d[f]:
yield (f,t)
def number_of_nodes(self):
return len(self.d)
def __repr__(self):
return self.d.__repr__()
def show(self):
dot = gv.Digraph()
for e in self.edges():
#print(e)
f, t = e
dot.edge(str(f), str(t), label='')
#print(dot.source)
show(dot)
# displays graph with graphviz
def show(dot, show=True, file_name='graph.gv'):
dot.render(file_name, view=show)
def showGraph(g,label="",directed=True):
if directed:
dot = gv.Digraph()
else:
dot = gv.Graph()
for e in g.edges():
print(e)
f, t = e
dot.edge(str(f), str(t), label=label)
print(dot.source)
show(dot)
def bit():
G = DGraph()
G.add_edge(("Blade","Samara"))
G.add_edge(("Shadow","Wolfe"))
G.add_edge(("Raven", "Austin"))
G.add_edge(("Blade", "Alice"))
G.add_edge(("Alice","Brandon"))
G.add_edge(("Blade", "Wolfe"))
G.add_edge(("Samara", "Robin"))
G.add_edge(("Samara", "Raven"))
G.add_edge(("Samara", "Hamed"))
G.add_edge(("Wolfe", "Blade"))
G.add_edge(("Hamed", "Samara"))
G.add_edge(("Wolfe", "Shadow"))
G.add_edge(("Brandon", "Brandon"))
G.add_edge(("Hamed", "Hamed"))
G.add_edge(("Austin", "Austin"))
showGraph(G, label="bit")
bit()
def bitten():
G=DGraph()
G.add_edge(("Samara","Blade"))
G.add_edge(("Wolfe","Shadow"))
G.add_edge(("Austin", "Raven"))
G.add_edge(("Alice","Blade"))
G.add_edge(("Brandon", "Alice"))
G.add_edge(("Wolfe", "Blade" ))
G.add_edge(("Robin", "Samara"))
G.add_edge(("Raven", "Samara"))
G.add_edge(("Hamed", "Samara"))
G.add_edge(("Blade", "Wolfe"))
G.add_edge(("Samara", "Hamed"))
G.add_edge(("Shadow", "Wolfe"))
G.add_edge(("Brandon", "Brandon"))
G.add_edge(("Hamed", "Hamed"))
G.add_edge(("Austin", "Austin"))
showGraph(G, label="bitten by")
#bitten()
family = ["Blade", "Samara", "Shadow", "Wolfe", "Raven", "Alice"]
"""
#Do transitive closure call out and the
#matrix power operation should be the same
D = nx.DiGraph()
#D.add_nodes_from("SamaraBladeWolfeShadowAliceRavenBrandonRobinHamedAustin")
D.add_edge("Blade","Samara")
D.add_edge("Shadow","Wolfe")
D.add_edge("Raven", "Austin")
D.add_edge("Blade", "Alice")
D.add_edge("Alice","Brandon")
D.add_edge("Blade", "Wolfe")
D.add_edge("Samara", "Robin")
D.add_edge("Samara", "Raven")
D.add_edge("Samara", "Hamed")
D.add_edge("Wolfe", "Blade")
D.add_edge("Hamed", "Samara")
D.add_edge("Wolfe", "Shadow")
D.add_edge("Brandon", "Brandon")
D.add_edge("Hamed", "Hamed")
D.add_edge("Austin", "Austin")
T = transitive_closure(D)
for e in D.edges(): print(e)
for n in D.nodes(): print(n)
def show(H):
nx.draw(H, with_labels=True, font_weight='bold')
plt.show()
#Use nx.to_numpy_matrix instead of nx.adjacency_matrix
# M = nx.adjacency_matrix(D)
# MT = nx.adjacency_matrix(T)
M = nx.to_numpy_matrix(D)
MT = nx.to_numpy_matrix(T)
def mPower(M, k): #M is numpy matrix
assert k >= 1
P = M
for _ in range(k):
P = P @ M
return P
def tc(M):
#compute transitive closure
pass
D1 = nx.DiGraph(M)
D2 = nx.DiGraph(M2)
print('Matrix for Original\n', M)
N = nx.to_numpy_array(D,dtype=int)
print('np_array for Original\n', N)
print('\nMatrix for Transitive Closure\n', MT)
N2 = nx.to_numpy_array(T,dtype=int)
print('np_array for Transitive Closure\n', N2)
show(D) #can use D, T, and numpy matrix power operation
show(T)
show(T)

hex to rgb

CodeCatch
0 likes • Nov 19, 2022
Python
def hex_to_rgb(hex):
return tuple(int(hex[i:i+2], 16) for i in (0, 2, 4))
hex_to_rgb('FFA501') # (255, 165, 1)

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

Python Fibonacci

JoeCamRoberon
0 likes • Sep 6, 2020
Python
def Fibonacci(n):
if n<0:
print("Incorrect input")
# First Fibonacci number is 0
elif n==1:
return 0
# Second Fibonacci number is 1
elif n==2:
return 1
else:
return Fibonacci(n-1)+Fibonacci(n-2)
# Driver Program
print(Fibonacci(9))