import pandas as pd
import altair as alt

from vega_datasets import data
cars = data.cars()
cars.head()

	Name	Miles_per_Gallon	Cylinders	Displacement	Horsepower	Weight_in_lbs	Acceleration	Year	Origin
0	chevrolet chevelle malibu	18.0	8	307.0	130.0	3504	12.0	1970-01-01	USA
1	buick skylark 320	15.0	8	350.0	165.0	3693	11.5	1970-01-01	USA
2	plymouth satellite	18.0	8	318.0	150.0	3436	11.0	1970-01-01	USA
3	amc rebel sst	16.0	8	304.0	150.0	3433	12.0	1970-01-01	USA
4	ford torino	17.0	8	302.0	140.0	3449	10.5	1970-01-01	USA

(cars
    .assign(
         Miles_per_Gallon = cars.Miles_per_Gallon * 1.609 / 3.785, # milhas por galão -> km por litro
         Displacement = cars.Displacement * 1.609,                 # milhas -> km
         Weight_in_lbs = cars.Weight_in_lbs * 0.454                # libras -> kg
    )
    .rename(columns={
        'Name':'Nome',
        'Miles_per_Gallon':'Quilometros_por_litro',
        'Cylinders':'Cilindros',
        'Displacement':'Deslocamento_kg',
        'Horsepower':'Potencia_cv',
        'Weight_in_lbs':'Peso_kg',
        'Acceleration':'Aceleracao_s',
        'Year':'Ano',
        'Origin':'Origem'
    }
    )     
)

	Nome	Quilometros_por_litro	Cilindros	Deslocamento_kg	Potencia_cv	Peso_kg	Aceleracao_s	Ano	Origem
0	chevrolet chevelle malibu	7.651783	8	493.963	130.0	1590.816	12.0	1970-01-01	USA
1	buick skylark 320	6.376486	8	563.150	165.0	1676.622	11.5	1970-01-01	USA
2	plymouth satellite	7.651783	8	511.662	150.0	1559.944	11.0	1970-01-01	USA
3	amc rebel sst	6.801585	8	489.136	150.0	1558.582	12.0	1970-01-01	USA
4	ford torino	7.226684	8	485.918	140.0	1565.846	10.5	1970-01-01	USA
...	...	...	...	...	...	...	...	...	...
401	ford mustang gl	11.477675	4	225.260	86.0	1266.660	15.6	1982-01-01	USA
402	vw pickup	18.704359	4	156.073	52.0	967.020	24.6	1982-01-01	Europe
403	dodge rampage	13.603170	4	217.215	84.0	1041.930	11.6	1982-01-01	USA
404	ford ranger	11.902774	4	193.080	79.0	1191.750	18.6	1982-01-01	USA
405	chevy s-10	13.178071	4	191.471	82.0	1234.880	19.4	1982-01-01	USA

406 rows × 9 columns