# Default Arguments (Functions)

This is a follow up to Use and Modify.

Allowing `a`

and `b`

to be passed as arguments to `get_mass_from_length()`

made the function more flexible, but for some types of dinosaurs we donâ€™t have specific values of `a`

and `b`

and so we have to use general values that can be applied to a number of different species.

Rewrite your `get_mass_from length()`

function from Use and Modify so that its arguments have default values of `a = 39.9`

and `b = 2.6`

(the average values from Seebacher 2001).

- Use this function to estimate the mass of a Sauropoda (
`a = 214.44`

,`b = 1.46`

) that is 22 m long (by setting`a`

and`b`

when calling the function). - Use this function to estimate the mass of a dinosaur from an unknown taxonomic group that is 16m long.
Only pass the function
`length`

, not`a`

and`b`

, so that the default values are used.

*Expected outputs for Default Arguments:*

*1*