Conditionally Calculate Max and Min Values of a Column
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I have a dataframe as below:
row_no stock_name last_price Var1
1 SAIL 501.00 0
2 SAIL 501.60 23
3 SAIL 500.00 0
4 SAIL 499.10 0
5 SAIL 499.40 0
6 SAIL 499.40 0
7 SAIL 502.00 0
8 SAIL 497.95 0
9 SAIL 495.55 20
10 SAIL 496.75 0
11 SAIL 496.75 0
12 SAIL 513.00 0
13 SAIL 497.00 0
14 SAIL 497.20 0
15 SAIL 497.00 0
16 SAIL 494.00 0
17 SAIL 497.00 0
18 SAIL 497.00 0
19 SAIL 497.00 0
20 SAIL 496.60 -9
21 SAIL 497.25 0
Need to Calculate Max and Min last_price when Var1 is not Zero.
When current Var1 is not equal to Zero, Max & Min last_price to be calculated between previous non zero value of Var1.
Example:
For Row No 9: Max last_price to be calculated as Max(last_price from row 9 to row 2) = 502 and Min last_price as Min(last_price from row 9 to row 2) = 495.55
I want the final dataframe as below:
row_no stock_name last_price Var1 Max_LTP Min_LTP
1 SAIL 501 0 0 0 0
2 SAIL 501.6 23 501.6 501
3 SAIL 500 0 0 0 0
4 SAIL 499.1 0 0 0
5 SAIL 499.4 0 0 0
6 SAIL 499.4 0 0 0
7 SAIL 502 0 0 0 0
8 SAIL 497.95 0 0 0
9 SAIL 495.55 20 502 495.55
10 SAIL 496.75 0 0 0
11 SAIL 496.75 0 0 0
12 SAIL 513 0 0 0 0
13 SAIL 497 0 0 0 0
14 SAIL 497.2 0 0 0
15 SAIL 497 0 0 0 0
16 SAIL 494 0 0 0 0
17 SAIL 497 0 0 0 0
18 SAIL 497 0 0 0 0
19 SAIL 497 0 0 0 0
20 SAIL 496.6 -9 513 494
21 SAIL 497.25 0 0 0 0
python python-3.x pandas dataframe list-comprehension
add a comment |
I have a dataframe as below:
row_no stock_name last_price Var1
1 SAIL 501.00 0
2 SAIL 501.60 23
3 SAIL 500.00 0
4 SAIL 499.10 0
5 SAIL 499.40 0
6 SAIL 499.40 0
7 SAIL 502.00 0
8 SAIL 497.95 0
9 SAIL 495.55 20
10 SAIL 496.75 0
11 SAIL 496.75 0
12 SAIL 513.00 0
13 SAIL 497.00 0
14 SAIL 497.20 0
15 SAIL 497.00 0
16 SAIL 494.00 0
17 SAIL 497.00 0
18 SAIL 497.00 0
19 SAIL 497.00 0
20 SAIL 496.60 -9
21 SAIL 497.25 0
Need to Calculate Max and Min last_price when Var1 is not Zero.
When current Var1 is not equal to Zero, Max & Min last_price to be calculated between previous non zero value of Var1.
Example:
For Row No 9: Max last_price to be calculated as Max(last_price from row 9 to row 2) = 502 and Min last_price as Min(last_price from row 9 to row 2) = 495.55
I want the final dataframe as below:
row_no stock_name last_price Var1 Max_LTP Min_LTP
1 SAIL 501 0 0 0 0
2 SAIL 501.6 23 501.6 501
3 SAIL 500 0 0 0 0
4 SAIL 499.1 0 0 0
5 SAIL 499.4 0 0 0
6 SAIL 499.4 0 0 0
7 SAIL 502 0 0 0 0
8 SAIL 497.95 0 0 0
9 SAIL 495.55 20 502 495.55
10 SAIL 496.75 0 0 0
11 SAIL 496.75 0 0 0
12 SAIL 513 0 0 0 0
13 SAIL 497 0 0 0 0
14 SAIL 497.2 0 0 0
15 SAIL 497 0 0 0 0
16 SAIL 494 0 0 0 0
17 SAIL 497 0 0 0 0
18 SAIL 497 0 0 0 0
19 SAIL 497 0 0 0 0
20 SAIL 496.6 -9 513 494
21 SAIL 497.25 0 0 0 0
python python-3.x pandas dataframe list-comprehension
subset a df where Var1 !=0 and then do what you need to do
– Ken Dekalb
Nov 23 '18 at 16:13
add a comment |
I have a dataframe as below:
row_no stock_name last_price Var1
1 SAIL 501.00 0
2 SAIL 501.60 23
3 SAIL 500.00 0
4 SAIL 499.10 0
5 SAIL 499.40 0
6 SAIL 499.40 0
7 SAIL 502.00 0
8 SAIL 497.95 0
9 SAIL 495.55 20
10 SAIL 496.75 0
11 SAIL 496.75 0
12 SAIL 513.00 0
13 SAIL 497.00 0
14 SAIL 497.20 0
15 SAIL 497.00 0
16 SAIL 494.00 0
17 SAIL 497.00 0
18 SAIL 497.00 0
19 SAIL 497.00 0
20 SAIL 496.60 -9
21 SAIL 497.25 0
Need to Calculate Max and Min last_price when Var1 is not Zero.
When current Var1 is not equal to Zero, Max & Min last_price to be calculated between previous non zero value of Var1.
Example:
For Row No 9: Max last_price to be calculated as Max(last_price from row 9 to row 2) = 502 and Min last_price as Min(last_price from row 9 to row 2) = 495.55
I want the final dataframe as below:
row_no stock_name last_price Var1 Max_LTP Min_LTP
1 SAIL 501 0 0 0 0
2 SAIL 501.6 23 501.6 501
3 SAIL 500 0 0 0 0
4 SAIL 499.1 0 0 0
5 SAIL 499.4 0 0 0
6 SAIL 499.4 0 0 0
7 SAIL 502 0 0 0 0
8 SAIL 497.95 0 0 0
9 SAIL 495.55 20 502 495.55
10 SAIL 496.75 0 0 0
11 SAIL 496.75 0 0 0
12 SAIL 513 0 0 0 0
13 SAIL 497 0 0 0 0
14 SAIL 497.2 0 0 0
15 SAIL 497 0 0 0 0
16 SAIL 494 0 0 0 0
17 SAIL 497 0 0 0 0
18 SAIL 497 0 0 0 0
19 SAIL 497 0 0 0 0
20 SAIL 496.6 -9 513 494
21 SAIL 497.25 0 0 0 0
python python-3.x pandas dataframe list-comprehension
I have a dataframe as below:
row_no stock_name last_price Var1
1 SAIL 501.00 0
2 SAIL 501.60 23
3 SAIL 500.00 0
4 SAIL 499.10 0
5 SAIL 499.40 0
6 SAIL 499.40 0
7 SAIL 502.00 0
8 SAIL 497.95 0
9 SAIL 495.55 20
10 SAIL 496.75 0
11 SAIL 496.75 0
12 SAIL 513.00 0
13 SAIL 497.00 0
14 SAIL 497.20 0
15 SAIL 497.00 0
16 SAIL 494.00 0
17 SAIL 497.00 0
18 SAIL 497.00 0
19 SAIL 497.00 0
20 SAIL 496.60 -9
21 SAIL 497.25 0
Need to Calculate Max and Min last_price when Var1 is not Zero.
When current Var1 is not equal to Zero, Max & Min last_price to be calculated between previous non zero value of Var1.
Example:
For Row No 9: Max last_price to be calculated as Max(last_price from row 9 to row 2) = 502 and Min last_price as Min(last_price from row 9 to row 2) = 495.55
I want the final dataframe as below:
row_no stock_name last_price Var1 Max_LTP Min_LTP
1 SAIL 501 0 0 0 0
2 SAIL 501.6 23 501.6 501
3 SAIL 500 0 0 0 0
4 SAIL 499.1 0 0 0
5 SAIL 499.4 0 0 0
6 SAIL 499.4 0 0 0
7 SAIL 502 0 0 0 0
8 SAIL 497.95 0 0 0
9 SAIL 495.55 20 502 495.55
10 SAIL 496.75 0 0 0
11 SAIL 496.75 0 0 0
12 SAIL 513 0 0 0 0
13 SAIL 497 0 0 0 0
14 SAIL 497.2 0 0 0
15 SAIL 497 0 0 0 0
16 SAIL 494 0 0 0 0
17 SAIL 497 0 0 0 0
18 SAIL 497 0 0 0 0
19 SAIL 497 0 0 0 0
20 SAIL 496.6 -9 513 494
21 SAIL 497.25 0 0 0 0
python python-3.x pandas dataframe list-comprehension
python python-3.x pandas dataframe list-comprehension
edited Nov 23 '18 at 16:31
Pravat
asked Nov 23 '18 at 16:11
PravatPravat
9310
9310
subset a df where Var1 !=0 and then do what you need to do
– Ken Dekalb
Nov 23 '18 at 16:13
add a comment |
subset a df where Var1 !=0 and then do what you need to do
– Ken Dekalb
Nov 23 '18 at 16:13
subset a df where Var1 !=0 and then do what you need to do
– Ken Dekalb
Nov 23 '18 at 16:13
subset a df where Var1 !=0 and then do what you need to do
– Ken Dekalb
Nov 23 '18 at 16:13
add a comment |
1 Answer
1
active
oldest
votes
Using Var1 with shift
and cumsum
create the group key , then groupby
, and assign the min
and max
value back to the original dataframe
mask=df.Var1.ne(0).shift().fillna(0).cumsum()
s=df.groupby(mask).last_price.agg(['min','max'])
s=s[df['Var1'].ne(0).groupby(mask).agg('any')]
s.index=df.index[df.Var1.ne(0)]
df[['Min_LTP','Max_LTP']]=s
df
Out[274]:
row_no stock_name last_price Var1 Max_LTP Min_LTP
0 1 SAIL 501.00 0 NaN NaN
1 2 SAIL 501.60 23 501.6 501.00
2 3 SAIL 500.00 0 NaN NaN
3 4 SAIL 499.10 0 NaN NaN
4 5 SAIL 499.40 0 NaN NaN
5 6 SAIL 499.40 0 NaN NaN
6 7 SAIL 502.00 0 NaN NaN
7 8 SAIL 497.95 0 NaN NaN
8 9 SAIL 495.55 20 502.0 495.55
9 10 SAIL 496.75 0 NaN NaN
10 11 SAIL 496.75 0 NaN NaN
11 12 SAIL 513.00 0 NaN NaN
12 13 SAIL 497.00 0 NaN NaN
13 14 SAIL 497.20 0 NaN NaN
14 15 SAIL 497.00 0 NaN NaN
15 16 SAIL 494.00 0 NaN NaN
16 17 SAIL 497.00 0 NaN NaN
17 18 SAIL 497.00 0 NaN NaN
18 19 SAIL 497.00 0 NaN NaN
19 20 SAIL 496.60 -9 513.0 494.00
20 21 SAIL 497.25 0 NaN NaN
add a comment |
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1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
Using Var1 with shift
and cumsum
create the group key , then groupby
, and assign the min
and max
value back to the original dataframe
mask=df.Var1.ne(0).shift().fillna(0).cumsum()
s=df.groupby(mask).last_price.agg(['min','max'])
s=s[df['Var1'].ne(0).groupby(mask).agg('any')]
s.index=df.index[df.Var1.ne(0)]
df[['Min_LTP','Max_LTP']]=s
df
Out[274]:
row_no stock_name last_price Var1 Max_LTP Min_LTP
0 1 SAIL 501.00 0 NaN NaN
1 2 SAIL 501.60 23 501.6 501.00
2 3 SAIL 500.00 0 NaN NaN
3 4 SAIL 499.10 0 NaN NaN
4 5 SAIL 499.40 0 NaN NaN
5 6 SAIL 499.40 0 NaN NaN
6 7 SAIL 502.00 0 NaN NaN
7 8 SAIL 497.95 0 NaN NaN
8 9 SAIL 495.55 20 502.0 495.55
9 10 SAIL 496.75 0 NaN NaN
10 11 SAIL 496.75 0 NaN NaN
11 12 SAIL 513.00 0 NaN NaN
12 13 SAIL 497.00 0 NaN NaN
13 14 SAIL 497.20 0 NaN NaN
14 15 SAIL 497.00 0 NaN NaN
15 16 SAIL 494.00 0 NaN NaN
16 17 SAIL 497.00 0 NaN NaN
17 18 SAIL 497.00 0 NaN NaN
18 19 SAIL 497.00 0 NaN NaN
19 20 SAIL 496.60 -9 513.0 494.00
20 21 SAIL 497.25 0 NaN NaN
add a comment |
Using Var1 with shift
and cumsum
create the group key , then groupby
, and assign the min
and max
value back to the original dataframe
mask=df.Var1.ne(0).shift().fillna(0).cumsum()
s=df.groupby(mask).last_price.agg(['min','max'])
s=s[df['Var1'].ne(0).groupby(mask).agg('any')]
s.index=df.index[df.Var1.ne(0)]
df[['Min_LTP','Max_LTP']]=s
df
Out[274]:
row_no stock_name last_price Var1 Max_LTP Min_LTP
0 1 SAIL 501.00 0 NaN NaN
1 2 SAIL 501.60 23 501.6 501.00
2 3 SAIL 500.00 0 NaN NaN
3 4 SAIL 499.10 0 NaN NaN
4 5 SAIL 499.40 0 NaN NaN
5 6 SAIL 499.40 0 NaN NaN
6 7 SAIL 502.00 0 NaN NaN
7 8 SAIL 497.95 0 NaN NaN
8 9 SAIL 495.55 20 502.0 495.55
9 10 SAIL 496.75 0 NaN NaN
10 11 SAIL 496.75 0 NaN NaN
11 12 SAIL 513.00 0 NaN NaN
12 13 SAIL 497.00 0 NaN NaN
13 14 SAIL 497.20 0 NaN NaN
14 15 SAIL 497.00 0 NaN NaN
15 16 SAIL 494.00 0 NaN NaN
16 17 SAIL 497.00 0 NaN NaN
17 18 SAIL 497.00 0 NaN NaN
18 19 SAIL 497.00 0 NaN NaN
19 20 SAIL 496.60 -9 513.0 494.00
20 21 SAIL 497.25 0 NaN NaN
add a comment |
Using Var1 with shift
and cumsum
create the group key , then groupby
, and assign the min
and max
value back to the original dataframe
mask=df.Var1.ne(0).shift().fillna(0).cumsum()
s=df.groupby(mask).last_price.agg(['min','max'])
s=s[df['Var1'].ne(0).groupby(mask).agg('any')]
s.index=df.index[df.Var1.ne(0)]
df[['Min_LTP','Max_LTP']]=s
df
Out[274]:
row_no stock_name last_price Var1 Max_LTP Min_LTP
0 1 SAIL 501.00 0 NaN NaN
1 2 SAIL 501.60 23 501.6 501.00
2 3 SAIL 500.00 0 NaN NaN
3 4 SAIL 499.10 0 NaN NaN
4 5 SAIL 499.40 0 NaN NaN
5 6 SAIL 499.40 0 NaN NaN
6 7 SAIL 502.00 0 NaN NaN
7 8 SAIL 497.95 0 NaN NaN
8 9 SAIL 495.55 20 502.0 495.55
9 10 SAIL 496.75 0 NaN NaN
10 11 SAIL 496.75 0 NaN NaN
11 12 SAIL 513.00 0 NaN NaN
12 13 SAIL 497.00 0 NaN NaN
13 14 SAIL 497.20 0 NaN NaN
14 15 SAIL 497.00 0 NaN NaN
15 16 SAIL 494.00 0 NaN NaN
16 17 SAIL 497.00 0 NaN NaN
17 18 SAIL 497.00 0 NaN NaN
18 19 SAIL 497.00 0 NaN NaN
19 20 SAIL 496.60 -9 513.0 494.00
20 21 SAIL 497.25 0 NaN NaN
Using Var1 with shift
and cumsum
create the group key , then groupby
, and assign the min
and max
value back to the original dataframe
mask=df.Var1.ne(0).shift().fillna(0).cumsum()
s=df.groupby(mask).last_price.agg(['min','max'])
s=s[df['Var1'].ne(0).groupby(mask).agg('any')]
s.index=df.index[df.Var1.ne(0)]
df[['Min_LTP','Max_LTP']]=s
df
Out[274]:
row_no stock_name last_price Var1 Max_LTP Min_LTP
0 1 SAIL 501.00 0 NaN NaN
1 2 SAIL 501.60 23 501.6 501.00
2 3 SAIL 500.00 0 NaN NaN
3 4 SAIL 499.10 0 NaN NaN
4 5 SAIL 499.40 0 NaN NaN
5 6 SAIL 499.40 0 NaN NaN
6 7 SAIL 502.00 0 NaN NaN
7 8 SAIL 497.95 0 NaN NaN
8 9 SAIL 495.55 20 502.0 495.55
9 10 SAIL 496.75 0 NaN NaN
10 11 SAIL 496.75 0 NaN NaN
11 12 SAIL 513.00 0 NaN NaN
12 13 SAIL 497.00 0 NaN NaN
13 14 SAIL 497.20 0 NaN NaN
14 15 SAIL 497.00 0 NaN NaN
15 16 SAIL 494.00 0 NaN NaN
16 17 SAIL 497.00 0 NaN NaN
17 18 SAIL 497.00 0 NaN NaN
18 19 SAIL 497.00 0 NaN NaN
19 20 SAIL 496.60 -9 513.0 494.00
20 21 SAIL 497.25 0 NaN NaN
answered Nov 23 '18 at 16:23
Wen-BenWen-Ben
124k83771
124k83771
add a comment |
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subset a df where Var1 !=0 and then do what you need to do
– Ken Dekalb
Nov 23 '18 at 16:13