Why does the value changes after set_index?
import pandas as pd
df = pd.read_csv('node.txt', header=None)
df = df.sort_values([1, 2, 3], ascending=[False, False, True])
dff2 = df
df = df.reset_index(drop=True)
dff = df
I tried to sort the columns in order of column number and checked the dataframe dff2
and dff
.
However, after the reset_index
method the values in column are little different.
dff2
dff
python-3.x pandas
add a comment |
import pandas as pd
df = pd.read_csv('node.txt', header=None)
df = df.sort_values([1, 2, 3], ascending=[False, False, True])
dff2 = df
df = df.reset_index(drop=True)
dff = df
I tried to sort the columns in order of column number and checked the dataframe dff2
and dff
.
However, after the reset_index
method the values in column are little different.
dff2
dff
python-3.x pandas
2
Could you post a reproducible example as text, not images? In the meantime, try rerunning your code, but withdff2 = df.copy()
instead ofdff2 = df
.
– Peter Leimbigler
Nov 20 '18 at 3:16
It works. thank you! Is there a reason why you recommended .copy() method?
– Kevin Nam
Nov 20 '18 at 7:18
From the python docs (docs.python.org/3/library/copy.html): Assignment statements in Python do not copy objects, they create bindings between a target and an object. For collections that are mutable or contain mutable items, a copy is sometimes needed so one can change one copy without changing the other.
– Peter Leimbigler
Nov 20 '18 at 13:41
add a comment |
import pandas as pd
df = pd.read_csv('node.txt', header=None)
df = df.sort_values([1, 2, 3], ascending=[False, False, True])
dff2 = df
df = df.reset_index(drop=True)
dff = df
I tried to sort the columns in order of column number and checked the dataframe dff2
and dff
.
However, after the reset_index
method the values in column are little different.
dff2
dff
python-3.x pandas
import pandas as pd
df = pd.read_csv('node.txt', header=None)
df = df.sort_values([1, 2, 3], ascending=[False, False, True])
dff2 = df
df = df.reset_index(drop=True)
dff = df
I tried to sort the columns in order of column number and checked the dataframe dff2
and dff
.
However, after the reset_index
method the values in column are little different.
dff2
dff
python-3.x pandas
python-3.x pandas
edited Nov 20 '18 at 8:10


Aqueous Carlos
293213
293213
asked Nov 20 '18 at 2:17


Kevin NamKevin Nam
113
113
2
Could you post a reproducible example as text, not images? In the meantime, try rerunning your code, but withdff2 = df.copy()
instead ofdff2 = df
.
– Peter Leimbigler
Nov 20 '18 at 3:16
It works. thank you! Is there a reason why you recommended .copy() method?
– Kevin Nam
Nov 20 '18 at 7:18
From the python docs (docs.python.org/3/library/copy.html): Assignment statements in Python do not copy objects, they create bindings between a target and an object. For collections that are mutable or contain mutable items, a copy is sometimes needed so one can change one copy without changing the other.
– Peter Leimbigler
Nov 20 '18 at 13:41
add a comment |
2
Could you post a reproducible example as text, not images? In the meantime, try rerunning your code, but withdff2 = df.copy()
instead ofdff2 = df
.
– Peter Leimbigler
Nov 20 '18 at 3:16
It works. thank you! Is there a reason why you recommended .copy() method?
– Kevin Nam
Nov 20 '18 at 7:18
From the python docs (docs.python.org/3/library/copy.html): Assignment statements in Python do not copy objects, they create bindings between a target and an object. For collections that are mutable or contain mutable items, a copy is sometimes needed so one can change one copy without changing the other.
– Peter Leimbigler
Nov 20 '18 at 13:41
2
2
Could you post a reproducible example as text, not images? In the meantime, try rerunning your code, but with
dff2 = df.copy()
instead of dff2 = df
.– Peter Leimbigler
Nov 20 '18 at 3:16
Could you post a reproducible example as text, not images? In the meantime, try rerunning your code, but with
dff2 = df.copy()
instead of dff2 = df
.– Peter Leimbigler
Nov 20 '18 at 3:16
It works. thank you! Is there a reason why you recommended .copy() method?
– Kevin Nam
Nov 20 '18 at 7:18
It works. thank you! Is there a reason why you recommended .copy() method?
– Kevin Nam
Nov 20 '18 at 7:18
From the python docs (docs.python.org/3/library/copy.html): Assignment statements in Python do not copy objects, they create bindings between a target and an object. For collections that are mutable or contain mutable items, a copy is sometimes needed so one can change one copy without changing the other.
– Peter Leimbigler
Nov 20 '18 at 13:41
From the python docs (docs.python.org/3/library/copy.html): Assignment statements in Python do not copy objects, they create bindings between a target and an object. For collections that are mutable or contain mutable items, a copy is sometimes needed so one can change one copy without changing the other.
– Peter Leimbigler
Nov 20 '18 at 13:41
add a comment |
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2
Could you post a reproducible example as text, not images? In the meantime, try rerunning your code, but with
dff2 = df.copy()
instead ofdff2 = df
.– Peter Leimbigler
Nov 20 '18 at 3:16
It works. thank you! Is there a reason why you recommended .copy() method?
– Kevin Nam
Nov 20 '18 at 7:18
From the python docs (docs.python.org/3/library/copy.html): Assignment statements in Python do not copy objects, they create bindings between a target and an object. For collections that are mutable or contain mutable items, a copy is sometimes needed so one can change one copy without changing the other.
– Peter Leimbigler
Nov 20 '18 at 13:41