import pandas as pd
pd.options.display.float_format="${:,.2f}".format
df = pd.DataFrame([123.4567, 234.5678, 345.6789, 456.7890],
index=['foo','bar','baz','quux'],
columns=['cost'])
print(df)
yields
cost
foo $123.46
bar $234.57
baz $345.68
quux $456.79
but this only works if you want every float to be formatted with a dollar sign.
Otherwise, if you want dollar formatting for some floats only, then I think you’ll have to pre-modify the dataframe (converting those floats to strings):
import pandas as pd
df = pd.DataFrame([123.4567, 234.5678, 345.6789, 456.7890],
index=['foo','bar','baz','quux'],
columns=['cost'])
df['foo'] = df['cost']
df['cost'] = df['cost'].map('${:,.2f}'.format)
print(df)
yields
cost foo
foo $123.46 123.4567
bar $234.57 234.5678
baz $345.68 345.6789
quux $456.79 456.7890