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combinations with python

I am trying to generate combination of ID's
Input: cid = SPARK
oupout: list of all the comibnations as below, position of each element should be constant. I am a beginner in python any help here is much appreciated.
'S****'
'S***K'
'S**R*'
'S**RK'
'S*A**'
'S*A*K'
'S*AR*'
'S*ARK'
'SP***'
'SP**K'
'SP*R*'
'SP*RK'
'SPA**'
'SPA*K'
'SPAR*'
'SPARK'
I tried below, I need a dynamic code:
cid = 'SPARK'
# print(cid.replace(cid[1],'*'))
# cu_len = lenth of cid [SPARK] here which is 5
# com_stars = how many stars i.e '*' or '**'
def cubiod_combo_gen(cu_len, com_stars, j_ite, i_ite):
cubiodList = []
crange = cu_len
i = i_ite #2 #3
j = j_ite #1
# com_stars = ['*','**','***','****']
while( i <= crange):
# print(j,i)
if len(com_stars) == 1:
x = len(com_stars)
n_cid = cid.replace(cid[j:i],com_stars)
i += x
j += x
cubiodList.append(n_cid)
elif len(com_stars) == 2:
x = len(com_stars)
n_cid = cid.replace(cid[j:i],com_stars)
i += x
j += x
cubiodList.append(n_cid)
elif len(com_stars) == 3:
x = len(com_stars)
n_cid = cid.replace(cid[j:i],com_stars)
i += x
j += x
cubiodList.append(n_cid)
return cubiodList
#print(i)
#print(n_cid)
# for item in cubiodList:
# print(item)
print(cubiod_combo_gen(5,'*',1,2))
print(cubiod_combo_gen(5,'**',1,3))

For every character in your given string, you can represent it as a binary string, using a 1 for a character that stays the same and a 0 for a character to replace with an asterisk.
def cubiod_combo_gen(string, count_star):
str_list = [char0 for char0 in string] # a list with the characters of the string
itercount = 2 ** (len(str_list)) # 2 to the power of the length of the input string
results = []
for config in range(itercount):
# return a string of i in binary representation
binary_repr = bin(config)[2:]
while len(binary_repr) < len(str_list):
binary_repr = '0' + binary_repr # add padding
# construct a list with asterisks
i = -1
result_list = str_list.copy() # soft copy, this made me spend like 10 minutes debugging lol
for char in binary_repr:
i += 1
if char == '0':
result_list[i] = '*'
if char == '1':
result_list[i] = str_list[i]
# now we have a possible string value
if result_list.count('*') == count_star:
# convert back to string and add to list of accepted strings
result = ''
for i in result_list:
result = result + i
results.append(result)
return results
# this function returns the value, so you have to use `print(cubiod_combo_gen(args))`
# comment this stuff out if you don't want an interactive user prompt
string = input('Enter a string : ')
count_star = input('Enter number of stars : ')
print(cubiod_combo_gen(string, int(count_star)))
It iterates through 16 characters in about 4 seconds and 18 characters in about 17 seconds. Also you made a typo on "cuboid" but I left the original spelling
Enter a string : DPSCT
Enter number of stars : 2
['**SCT', '*P*CT', '*PS*T', '*PSC*', 'D**CT', 'D*S*T', 'D*SC*', 'DP**T', 'DP*C*', 'DPS**']
As a side effect of this binary counting, the list is ordered by the asterisks, where the earliest asterisk takes precedence, with next earliest asterisks breaking ties.
If you want a cumulative count like 1, 4, 5, and 6 asterisks from for example "ABCDEFG", you can use something like
star_counts = (1, 4, 5, 6)
string = 'ABCDEFG'
for i in star_counts:
print(cubiod_combo_gen(string, star_counts))
If you want the nice formatting you have in your answer, try adding this block at the end of your code:
def formatted_cuboid(string, count_star):
values = cubiod_combo_gen(string, count_star)
for i in values:
print(values[i])
I honestly do not know what your j_ite and i_ite are, but it seems like they have no use so this should work. If you still want to pass these arguments, change the first line to def cubiod_combo_gen(string, count_star, *args, **kwargs):

I am not sure what com_stars does, but to produce your sample output, the following code does.
def cuboid_combo(cid):
fill_len = len(cid)-1
items = []
for i in range(2 ** fill_len):
binary = f'{i:0{fill_len}b}'
#print(binary, 'binary', 'num', i)
s = cid[0]
for idx, bit in enumerate(binary,start=1):
if bit == '0':
s += '*'
else: # 'bit' == 1
s += cid[idx]
items.append(s)
return items
#cid = 'ABCDEFGHI'
cid = 'DPSCT'
result = cuboid_combo(cid)
for item in result:
print(item)
Prints:
D****
D***T
D**C*
D**CT
D*S**
D*S*T
D*SC*
D*SCT
DP***
DP**T
DP*C*
DP*CT
DPS**
DPS*T
DPSC*
DPSCT

Finding the longest repetitive piece in a string python

I want to write a function "longest" where my input doc test looks like this (python)
"""
>>>longest('1211')
1
>>>longest('1212')
2
>>>longest('212111212112112121222222212212112121')
2
>>>lvs('1')
0
>>>lvs('121')
0
>>>lvs('12112')
0
"""
What I am trying to achieve is that for example in the first case the 1 is repeated in the back with "11" so the repeated part is 1 and this repeated part is 1 character long it is this length that this function should return.
So in the case of the second you got "1212" so the repeated part is "12" which is 2 characters long.
The tricky thing here is that the longest is "2222222" but this doesn't matter since it is not in the front nor the back. The solution for the last doc test is that 21 is being repeated which is 2 characters long.
The code I have created this far is following
import re
def repetitions(s):
r = re.compile(r"(.+?)\1+")
for match in r.finditer(s):
yield (match.group(1), len(match.group(0)) / len(match.group(1)))
def longest(s):
"""
>>> longest('1211')
1
"""
nummer_hoeveel_keer = dict(repetitions(s)) #gives a dictionary with as key the number (for doctest 1 this be 1) and as value the length of the key
if nummer_hoeveel_keer == {}: #if there are no repetitive nothing should be returnd
return 0
sleutels = nummer_hoeveel_keer.keys() #here i collect the keys to see which has has the longest length
lengtes = {}
for sleutel in sleutels:
lengte = len(sleutel)
lengtes[lengte] = sleutel
while lengtes != {}: #as long there isn't a match and the list isn't empty i keep looking for the longest repetitive which is or in the beginning or in the back
maximum_lengte = max(lengtes.keys())
lengte_sleutel = {v: k for k, v in lengtes.items()}
x= int(nummer_hoeveel_keer[(lengtes[maximum_lengte])])
achter = s[len(s) - maximum_lengte*x:]
voor = s[:maximum_lengte*x]
combinatie = lengtes[maximum_lengte]*x
if achter == combinatie or voor == combinatie:
return maximum_lengte
del lengtes[str(maximum_lengte)]
return 0
when following doc test is put in this code
"""
longest('12112')
0
""
there is a key error where I put "del lengtes[str(maximum_lengte)]"
after a suggestion of #theausome I used his code as a base to work further with (see answer): this makes my code right now look like this:
def longest(s):
if len(s) == 1:
return 0
longest_patt = []
k = s[-1]
longest_patt.append(k)
for c in s[-2::-1]:
if c != k:
longest_patt.append(c)
else:
break
rev_l = list(reversed(longest_patt))
character = ''.join(rev_l)
length = len(rev_l)
s = s.replace(' ','')[:-length]
if s[-length:] == character:
return len(longest_patt)
else:
return 0
l = longest(s)
print l
Still there are some doc tests that are troubling me like for example:
>>>longest('211211222212121111111')
3 #I get 1
>>>longest('2111222122222221211221222112211')
4 #I get 1
>>>longest('122211222221221112111')
4 #I get 1
>>>longest('121212222112222112')
6 #I get 1
Anyone has ideas how to deal with/ approach this problem, maybe find a more graceful way around the problem ?

Try the below code. It works perfectly for your input doc tests.
def longest(s):
if len(s) == 1:
return 0
longest_patt = []
k = s[-1]
longest_patt.append(k)
for c in s[-2::-1]:
if c != k:
longest_patt.append(c)
else:
break
rev_l = list(reversed(longest_patt))
character = ''.join(rev_l)
length = len(rev_l)
s = s.replace(' ','')[:-length]
if s[-length:] == character:
return len(longest_patt)
else:
return 0
l = longest(s)
print l
Output:
longest('1211')
1
longest('1212')
2
longest('212111212112112121222222212212112121')
2
longest('1')
0
longest('121')
0
longest('12112')
0

Python: Letters to numbers not working correctly

So I have this project for school and I am so close to finishing it but there is one that I just cant seem to get to work properly. One of the functions I have is:
vowels = "aeiou"
consonants = "bcdfghjklmnpqrstvwyz"
def alphapinDecode(tone):
s = tone.lower()
pin = ''
for ch in s:
if ch in consonants:
idx = consonants.find(ch)
elif ch in vowels:
idx2 = vowels.find(ch)
pin = str(pin) + str(idx*5 + idx2)
print(pin)
return None
For the most part the function runs exactly how I want it to. I take a string and it returns numbers as a string.
For example:
>>> alphapinDecode('bomelela')
3464140
But when I do this one:
>>>> alphapinDecode('bomeluco')
it returns 346448 instead of the 3464408 like it is supposed to do (according to my assignment). Now I know the function is giving me the correct answer based on the code, but what am I missing to have it include the 0 before the 8?
EDIT:
Function is supposed to take the string that you pass(tone) and break it up into 2 letter chunks(vowel/consonant pair). With the pair, it is supposed to use the pair and index them with vowels/consonants and return a number. >>>alphapinDecode('hi') returns 27 because consonants[h] gives idx = 5 while vowels[i] gives idx2 = 2

I think your lecture trying to test students coding adaptability.
If really want achieve some output like that please try like below
vowels = "aeiou"
consonants = "bcdfghjklmnpqrstvwyz"
def alphapinDecode(tone):
s = tone.lower()
pin = ''
for ch in s:
if ch in consonants:
idx = consonants.find(ch)
elif ch in vowels:
idx2 = vowels.find(ch)
num = '%02d' % int((idx*5) + idx2) #python 2
num = "{0:0=2d}".format((idx*5) + idx2) #python 3 more verbose
pin = pin + str(num)
print(int(pin))
return None
alphapinDecode('bomeluco') # 3464408
alphapinDecode('bomelela') # 3464140

Your approach is perhaps awkward - I would iterate two characters at a time:
def alphapinDecode(tone):
s = tone.lower()
pin = ''
# Step over the string two characters at a time
for i in range(0, len(s), 2):
ch1 = s[i]
ch2 = s[i+1]
if ch1 in consonants and ch2 in vowels:
idx1 = consonants.find(ch1)
idx2 = vowels.find(ch2)
this_pair = idx1*5 + idx2
# For debugging
print(this_pair)
pin = pin + str(this_pair)
# We need to print without leading zeroes
print(int(pin))
# Returning the pin as an integer is better, IMO
return int(pin)
OK, now we have the code looking a bit better, we can see, I hope, that for the co pair in your second text, the value is 1*5 + 3, which equals 8, of course, but you really want 08. There's a number of ways to do this, but since you're a beginner I'll illustrate the easiest way.
this_pair = idx1*5 + idx2
if this_pair < 10:
# If the pair is less than ten, prepend a leading zero
this_pair_pin = '0' + str(this_pair)
else
this_pair_pin = str(this_pair)
pin = pin + this_pair_pin
EDIT: Let's forget about accumulating the answer in a string as we can simplify the code:
pin = 0
#...
this_pair = idx1*5 + idx2
pin = pin * 100 + this_pair
print(pin)

How to convert numbers in a string without using lists?

My prof wants me to create a function that return the sum of numbers in a string but without using any lists or list methods.
The function should look like this when operating:
>>> sum_numbers('34 3 542 11')
590
Usually a function like this would be easy to create when using lists and list methods. But trying to do so without using them is a nightmare.
I tried the following code but they don't work:
>>> def sum_numbers(s):
for i in range(len(s)):
int(i)
total = s[i] + s[i]
return total
>>> sum_numbers('1 2 3')
'11'
Instead of getting 1, 2, and 3 all converted into integers and added together, I instead get the string '11'. In other words, the numbers in the string still have not been converted to integers.
I also tried using a map() function but I just got the same results:
>>> def sum_numbers(s):
for i in range(len(s)):
map(int, s[i])
total = s[i] + s[i]
return total
>>> sum_numbers('1 2 3')
'11'

Totally silly of course, but for fun:
s = '34 3 542 11'
n = ""; total = 0
for c in s:
if c == " ":
total = total + int(n)
n = ""
else:
n = n + c
# add the last number
total = total + int(n)
print(total)
> 590
This assumes all characters (apart from whitespaces) are figures.

You've definitely put some effort in here, but one part of your approach definitely won't work as-is: you're iterating over the characters in the string, but you keep trying to treat each character as its own number. I've written a (very commented) method that accomplishes what you want without using any lists or list methods:
def sum_numbers(s):
"""
Convert a string of numbers into a sum of those numbers.
:param s: A string of numbers, e.g. '1 -2 3.3 4e10'.
:return: The floating-point sum of the numbers in the string.
"""
def convert_s_to_val(s):
"""
Convert a string into a number. Will handle anything that
Python could convert to a float.
:param s: A number as a string, e.g. '123' or '8.3e-18'.
:return: The float value of the string.
"""
if s:
return float(s)
else:
return 0
# These will serve as placeholders.
sum = 0
current = ''
# Iterate over the string character by character.
for c in s:
# If the character is a space, we convert the current `current`
# into its numeric representation.
if c.isspace():
sum += convert_s_to_val(current)
current = ''
# For anything else, we accumulate into `current`.
else:
current = current + c
# Add `current`'s last value to the sum and return.
sum += convert_s_to_val(current)
return sum
Personally, I would use this one-liner, but it uses str.split():
def sum_numbers(s):
return sum(map(float, s.split()))

No lists were used (nor harmed) in the production of this answer:
def sum_string(string):
total = 0
if len(string):
j = string.find(" ") % len(string) + 1
total += int(string[:j]) + sum_string(string[j:])
return total
If the string is noisier than the OP indicates, then this should be more robust:
import re
def sum_string(string):
pattern = re.compile(r"[-+]?\d+")
total = 0
match = pattern.search(string)
while match:
total += int(match.group())
match = pattern.search(string, match.end())
return total
EXAMPLES
>>> sum_string('34 3 542 11')
590
>>> sum_string(' 34 4 ')
38
>>> sum_string('lksdjfa34adslkfja4adklfja')
38
>>> # and I threw in signs for fun
...
>>> sum_string('34 -2 45 -8 13')
82
>>>

If you want to be able to handle floats and negative numbers:
def sum_numbers(s):
sm = i = 0
while i < len(s):
t = ""
while i < len(s) and not s[i].isspace():
t += s[i]
i += 1
if t:
sm += float(t)
else:
i += 1
return sm
Which will work for all cases:
In [9]: sum_numbers('34 3 542 11')
Out[9]: 590.0
In [10]: sum_numbers('1.93 -1 23.12 11')
Out[10]: 35.05
In [11]: sum_numbers('')
Out[11]: 0
In [12]: sum_numbers('123456')
Out[12]: 123456.0
Or a variation taking slices:
def sum_numbers(s):
prev = sm = i = 0
while i < len(s):
while i < len(s) and not s[i].isspace():
i += 1
if i > prev:
sm += float(s[prev:i])
prev = i
i += 1
return sm
You could also use itertools.groupby which uses no lists, using a set of allowed chars to group by:
from itertools import groupby
def sum_numbers(s):
allowed = set("0123456789-.")
return sum(float("".join(v)) for k,v in groupby(s, key=allowed.__contains__) if k)
which gives you the same output:
In [14]: sum_numbers('34 3 542 11')
Out[14]: 590.0
In [15]: sum_numbers('1.93 -1 23.12 11')
Out[15]: 35.05
In [16]: sum_numbers('')
Out[16]: 0
In [17]: sum_numbers('123456')
Out[17]: 123456.0
Which if you only have to consider positive ints could just use str.isdigit as the key:
def sum_numbers(s):
return sum(int("".join(v)) for k,v in groupby(s, key=str.isdigit) if k)

Try this:
def sum_numbers(s):
sum = 0
#This string will represent each number
number_str = ''
for i in s:
if i == ' ':
#if it is a whitespace it means
#that we have a number so we incease the sum
sum += int(number_str)
number_str = ''
continue
number_str += i
else:
#add the last number
sum += int(number_str)
return sum

You could write a generator:
def nums(s):
idx=0
while idx<len(s):
ns=''
while idx<len(s) and s[idx].isdigit():
ns+=s[idx]
idx+=1
yield int(ns)
while idx<len(s) and not s[idx].isdigit():
idx+=1
>>> list(nums('34 3 542 11'))
[34, 3, 542, 11]
Then just sum that:
>>> sum(nums('34 3 542 11'))
590
or, you could use re.finditer with a regular expression and a generator construction:
>>> sum(int(m.group(1)) for m in re.finditer(r'(\d+)', '34 3 542 11'))
590
No lists used...

def sum_numbers(s):
total=0
gt=0 #grand total
l=len(s)
for i in range(l):
if(s[i]!=' '):#find each number
total = int(s[i])+total*10
if(s[i]==' ' or i==l-1):#adding to the grand total and also add the last number
gt+=total
total=0
return gt
print(sum_numbers('1 2 3'))
Here each substring is converted to number and added to grant total

If we omit the fact eval is evil, we can solve that problem with it.
def sum_numbers(s):
s = s.replace(' ', '+')
return eval(s)
Yes, that simple. But i won't put that thing in production.
And sure we need to test that:
from hypothesis import given
import hypothesis.strategies as st
#given(list_num=st.lists(st.integers(), min_size=1))
def test_that_thing(list_num):
assert sum_numbers(' '.join(str(i) for i in list_num)) == sum(list_num)
test_that_thing()
And it would raise nothing.

Write a program that prints the number of times the string contains a substring

s = "bobobobobobsdfsdfbob"
count = 0
for x in s :
if x == "bob" :
count += 1
print count
i want to count how many bobs in string s, the result if this gives me 17
what's wrong with my code i'm newbie python.

When you are looping overt the string, the throwaway variable will hold the characters, so in your loop x is never equal with bob.
If you want to count the non-overlaping strings you can simply use str.count:
In [52]: s.count('bob')
Out[52]: 4
For overlapping sub-strings you can use lookaround in regex:
In [57]: import re
In [59]: len(re.findall(r'(?=bob)', s))
Out[59]: 6

you can use string.count
for example:
s = "bobobobobobsdfsdfbob"
count = s.count("bob")
print(count)

I'm not giving the best solution, just trying to correct your code.
Understanding what for each (a.k.a range for) does in your case
for c in "Hello":
print c
Outputs:
H
e
l
l
o
In each iteration you are comparing a character to a string which results in a wrong answer.
Try something like
(For no overlapping, i.e no span)
s = "bobobobobobsdfsdfbob"
w = "bob"
count = 0
i = 0
while i <= len(s) - len(w):
if s[i:i+len(w)] == w:
count += 1
i += len(w)
else:
i += 1
print (count)
Output:
Count = 4
Overlapping
s = "bobobobobobsdfsdfbob"
w = "bob"
count = 0
for i in range(len(s) - len(w) + 1):
if s[i:i+len(w)] == w:
count += 1
print (count)
Output:
Count = 6