Data Science in Omics Introduction
An OMICS Course Part 1: Shell, Organizing and Genomics
Measures of the amount of energy used by biological processes are
critical to understanding many aspects of biology from cellular
physiology to ecosystem ecology. There are many different units for
energy use and their utilization varies across methods, research areas,
and lab groups. Write a function, convert_energy_units(energy_value,
input_unit, output_unit) to convert units between the following energy
values - Joules(J), Kilojoules(KJ), Calories(CAL), and Kilocalories
(KCAL; this is unit used for labeling the amount of energy contained in
food). A Kilojoule is 1000 Joules, a Calorie is 4.1868 Joules, a
Kilocalorie is 4186.8 Joules. An example of a call to this function
would look like:
energy_in_cals = 200
energy_in_joules = convert_energy_units(energy_in_cals, "CAL", "J")
Make this function more efficient by using ‘else if’ (elif) statements.
If either the input unit or the output unit do not match the five types
given above, have the function print - “Sorry, I don’t know how to
convert “ + the name of the unit provided. Use your function to answer
the following questions.
a. What is the daily metabolic energy used by a human (~2500 KCALs) in Joules.
b. How many times more energy does a common seal use than a human? The common seal uses ~52,500 KJ/day (Nagy et al. 1999). Use the daily human metabolic cost given above.
c. How many ergs (ERG) are there in one kilocalorie. [Since we didn’t include the erg conversion this should trigger our ‘don’t know how to convert’ message]
Instead of writing an individual conversion between each of the different currencies (which would require 12 if statements) you could choose to convert all of the input units to a common scale and then convert from that common scale to the output units. This approach is especially useful since we might need to add new units later and this will be much easier using this approach.