Python recursive index changing - python-3.x

I am trying to arrange matrix in way that it will dynamically change the indexes.
I have tried to do it by means of for loop, however it only does once for each index.
def arrangeMatrix(progMatrix):
for l in range(len(progMatrix)):
for item in range(len(progMatrix[l])):
if indexExists(progMatrix,l + 1,item) and progMatrix[l + 1][item] == " ":
progMatrix[l + 1][item] = progMatrix[l][item]
progMatrix[l][item] = " "
The original list is:
1 0 7 6 8
0 5 5 5
2 1 6
4 1 3 7
1 1 1 7 5
And my code should fill all gapped indexes from up to bottom, however my result is:
1 0 6 8
0 5 5
2 1 7
4 1 3 7 6
1 1 1 7 5 5
The actual result should be:
1 0
0 5 8
2 1 7 5
4 1 3 7 6 6
1 1 1 7 5 5
Any help or hint is appreciated.Thanks in advance

It is probably easier if you first iterate the columns, since the change that happens in one column is independent on what happens in other columns. Then, per column, you could iterate the cells from the bottom to the top and keep track of the y-coordinate where the next non-space should "drop down" to.
No recursion is needed.
Here is how that could be coded:
def arrangeMatrix(progMatrix):
for x in range(len(progMatrix[0])):
targetY = len(progMatrix)-1
for y in range(len(progMatrix)-1,-1,-1):
row = progMatrix[y]
if row[x] != " ": # Something to drop down
if y < targetY: # Is it really to drop any lower?
progMatrix[targetY][x] = row[x] # copy it down
row[x] = " " # ...and clear the cell where it dropped from
targetY -= 1 # since we filled the target cell, the next drop would be higher

Related

Cumulative count using grouping, sorting, and condition

i want Cumulative count of zero only in column c grouped by column a and sorted by b if other number the count reset to 1
this a sample
df = pd.DataFrame({'a':[1,1,1,1,2,2,2,2],
'b':[1,2,3,4,1,2,3,4],
'c':[10,0,0,5,1,0,1,0]}
)
i try next code that work but if zero appear more than one time shift function didn't depend on new value and need to run more than one time depend on count of zero series
df.loc[df.c == 0 ,'n'] = df.n.shift(1)+1
i try next code it done with small data frame but when try with large data take a long time and didn't finsh
for ind in df.index:
if df.loc[ind,'c'] == 0 :
df.loc[ind,'new'] = df.loc[ind-1,'new']+1
else :
df.loc[ind,'new'] = 1
pd.DataFrame({'a':[1,1,1,1,2,2,2,2],
'b':[1,2,3,4,1,2,3,4],
'c':[10,0,0,5,1,0,1,0]}
The desired result
a b c n
0 1 1 10 1
1 1 2 0 2
2 1 3 0 3
3 1 4 5 1
4 2 1 1 1
5 2 2 0 2
6 2 3 1 1
7 2 4 0 2
Try use cumsum to create a group variable and then use groupby.cumcount to create the new column:
df.sort_values(['a', 'b'], inplace=True)
df['n'] = df['c'].groupby([df.a, df['c'].ne(0).cumsum()]).cumcount() + 1
df
a b c n
0 1 1 10 1
1 1 2 0 2
2 1 3 0 3
3 1 4 5 1
4 2 1 1 1
5 2 2 0 2
6 2 3 1 1
7 2 4 0 2

recursive function does not work as expected

Could someone explain the code? I just can not understand why this code gives output like this:
1
3
6
10
15
21
I expected the code to give something like this:
1
3
5
7
9
11
What am I missing here?
def tri_recursion(k):
if(k > 0):
result = k + tri_recursion(k-1)
print(result)
else:
result = 0
return result
tri_recursion(6)
For your recursive function, the termination condition is k=0.
It's clear that if k=0, tri_recursion(0) = 0.
If k=1, tri_recursion(1) = 1 + tri_recursion(0), which from above, is 1 + 0 or 1.
If k=2, tri_recursion(2) = 2 + tri_recursion(1), which from above, is 2 + 1 or 3.
If k=3, tri_recursion(3) = 3 + tri_recursion(2), which from above, is 3 + 3 or 6.
If k=4, tri_recursion(4) = 5 + tri_recursion(3), which from above, is 4 + 6 or 10.
If k=5, tri_recursion(5) = 4 + tri_recursion(4), which from above, is 5 + 10 or 15.
If k=6, tri_recursion(6) = 6 + tri_recursion(5), which from above, is 6 + 15 or 21.
See the pattern?
Your code is calculating the sum of numbers up to n where n is 6 in the above case. The print statement prints the intermediate results. Hence the output 1 3 6 10 15 21.
1 - The sum of numbers from 0 to 1
3 - The sum of numbers from 0 to 2
6 - The sum of numbers from 0 to 3
10 - The sum of numbers from 0 to 4
15 - The sum of numbers from 0 to 5
21 - The sum of numbers from 0 to 6

How to recognize [1,X,X,X,1] repeating pattern in panda serie

I have a boolean column in a csv file for example:
1 1
2 0
3 0
4 0
5 1
6 1
7 1
8 0
9 0
10 1
11 0
12 0
13 1
14 0
15 1
You can see here 1 is reapting every 5 lines.
I want to recognize this repeating pattern [1,0,0,0] as soon as the repetition is above 10 in python (I have ~20.000 rows/file).
The pattern can start at any position
How could I manage this in python avoiding if .....
# Generate 20000 of 0s and 1s
data = pd.Series(np.random.randint(0, 2, 20000))
# Keep indices of 1s
idx = df[df > 0].index
# Check distance of current index with next index whether is 4 or not,
# Say if position 2 and position 6 is found as 1, so 6 - 2 = 4
found = []
for i, v in enumerate(idx):
if i == len(idx) - 1:
break
next_value = idx[i + 1]
if (next_value - v) == 4:
found.append(v)
print(found)

Function coverage () in R

I want to understand what the function coverage does to an IRange. for example the codes below:
ir <- IRanges (1:3, width = 3)
ir
IRanges object with 3 ranges and 0 metadata columns:
start end width
[1] 1 3 3
[2] 2 4 3
[3] 3 5 3
coverage (ir)
integer-Rle of length 5 with 5 runs
Lengths: 1 1 1 1 1
Values : 1 2 3 2 1
why the values repeats itself like 123 then 21
I figured it out.
The right answer is that we count the ranges covering each number starting from 1 till the last number in the last range.
for example
ir <- IRanges (4:6, width = 3)
first, we draw a plot for that IRange staring from 1 which is not included in any range and ending with 8 which is the boundry of the last range
second, we count the ranges of the Ir that covers each of these number from 0 to 8
count = c (0,0,0,1,2,3,2,1)
Rle (count)
numeric-Rle of length 8 with 6 runs
Lengths: 3 1 1 1 1 1
Values : 0 1 2 3 2 1

Octave position of maximum value in column

I want to find the argmax of the values in a matrix by column, e.g.:
1 2 3 2 3 3
4 5 6 ->
3 7 8
I feel like I should just be able to map an argmax/posmax function over the columns, but I don't see a particularly intuitive way to do this in Octave.
Read max function documentation here
[max_values indices] = max(input);
Example:
input =
1 2 3
4 5 6
3 7 8
[max_values indices] = max(input)
max_values =
4 7 8
indices =
2 3 3
In Octave If
A =
1 3 2
6 5 4
7 9 8
1) For Each Column Max value and corresponding index of them can be found by
>> [max_values,indices] =max(A,[],1)
max_values =
7 9 8
indices =
3 3 3
2) For Each Row Max value and corresponding index of them can be found by
>> [max_values,indices] =max(A,[],2)
max_values =
3
6
9
indices =
2
1
2
Similarly For minimum value
>> [min_values,indices] =min(A,[],1)
min_values =
1 3 2
indices =
1 1 1
>> [min_values,indices] =min(A,[],2)
min_values =
1
4
7
indices =
1
3
1

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