Python Forum

Hi,
I have below datframe with numerical column marks
df:

name age marks
A       14   12.34
B       12   34.1
C       29   19.567

I want to increase marks column decimals to 6

desired output:

name age marks
A       14   12.340000
B       12   34.100000
C       29   19.567000

I use below code but it did not change anything:

df['marks'] =df['marks'].round(6)

import pandas as pd
from io import StringIO

data = StringIO('''\
name age marks
A 14 12.34
B 12 34.1
C 29 19.567''')

df = pd.read_csv(data, sep=' ')

>>> df
  name  age   marks
0    A   14  12.340
1    B   12  34.100
2    C   29  19.567

>>> df['marks'] = df['marks'].map(lambda x: f'{x:.6f}')
>>> df
  name  age      marks
0    A   14  12.340000
1    B   12  34.100000
2    C   29  19.567000

You can set the number of significant digits pandas uses when printing.

import pandas as pd
pd.set_option('display.float_format', '{:.10f}'.format)

df = pd.DataFrame([1/x for x in range(1, 11)], columns=["values"])
df.to_csv("test.csv", index=False)
print(df)

Output:0 1.0000000000
1 0.5000000000
2 0.3333333333
3 0.2500000000
4 0.2000000000
5 0.1666666667
6 0.1428571429
7 0.1250000000
8 0.1111111111
9 0.1000000000

Unlike snippsat's solution this only changes how floats are printed, the values in the dataframe are unaltered.

SriRajesh

snippsat

deanhystad