Skip to main content

when predicate lambda

Nov 19, 2022CodeCatch
Loading...

More Python Posts

sum of powers

Nov 19, 2022CodeCatch

0 likes • 13 views

def sum_of_powers(end, power = 2, start = 1):
return sum([(i) ** power for i in range(start, end + 1)])
sum_of_powers(10) # 385
sum_of_powers(10, 3) # 3025
sum_of_powers(10, 3, 5) # 2925

Return Letter Combinations

Nov 18, 2022AustinLeath

0 likes • 0 views

# @return a list of strings, [s1, s2]
def letterCombinations(self, digits):
if '' == digits: return []
kvmaps = {
'2': 'abc',
'3': 'def',
'4': 'ghi',
'5': 'jkl',
'6': 'mno',
'7': 'pqrs',
'8': 'tuv',
'9': 'wxyz'
}
return reduce(lambda acc, digit: [x + y for x in acc for y in kvmaps[digit]], digits, [''])

Convert Decimal to Binary and Hexadecimal

May 31, 2023CodeCatch

0 likes • 0 views

# Prompt user for a decimal number
decimal = int(input("Enter a decimal number: "))
# Convert decimal to binary
binary = bin(decimal)
# Convert decimal to hexadecimal
hexadecimal = hex(decimal)
# Display the results
print("Binary:", binary)
print("Hexadecimal:", hexadecimal)

lambda example

Nov 19, 2022CodeCatch

0 likes • 3 views

list_1 = [1,2,3,4,5,6,7,8,9]
cubed = map(lambda x: pow(x,3), list_1)
print(list(cubed))
#Results
#[1, 8, 27, 64, 125, 216, 343, 512, 729]

Using logic with sets

Nov 18, 2022AustinLeath

0 likes • 1 view

#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}
'''

print indices

Nov 18, 2022AustinLeath

0 likes • 0 views

# List
lst = [1, 2, 3, 'Alice', 'Alice']
# One-Liner
indices = [i for i in range(len(lst)) if lst[i]=='Alice']
# Result
print(indices)
# [3, 4]