Homework #3 EP476: Introduction to Scientific Computing for Engineering Physics

Due: Tuesday, April 12, 1:00 PM

This assignment will have you read some data from a file and into data structures in memory. Two related but slightly different data files will be used.

PROBLEM 1 Start a new repository for this assignment. Copy and paste the text of this page into a README file for this repo, commit that file to the master branch and push it to the github repository. Element Library

The first file is a list of natural abundances for each element. A sample file is provided here. The simple format has one block for each element, in which the first line of each block contains:

the chemical symbol
the molar mass (g/mol)
the atomic number
the density at standard temperature and pressure (g/cc)
the number of naturally occurring isotopes that make up that element

The rest of the block has one line per isotope, with each line containing:

the mass number of the isotope
the atomic abundance

PROBLEM 2 Create a branch from the master branch called elelib_basic.

PROBLEM 3 Write a module that provides functions to read an element library into a single data structure. Assume that there will be no blank lines or comments. This module should include:

one function to parse the first line each block
one function to parse a single isotope abundance line in a block
one function to open the file and loop over the lines, calling the other functions

You should also write nose tests for each of the first two functions.

PROBLEM 4 Commit any necessary files to the repository and push this branch to github. Do not merge this into the master branch. Material Library

This file is a list of engineering materials. A sample file is provided here. The simple format has one block for each material, in which the first line of each block contains:

the name of the material
the density at standard temperature and pressure (g/cc)
the number of elements that make up the material

The rest of the block has one line per element, with each line containing:

the chemcial symbol
the mass fraction of that element
the atomic number of the element

PROBLEM 5 Create a branch from the elelib_basic branch called matlib_basic.

PROBLEM 6 Write a module that provides functions to read a material library into a single data structure. Assume that there will be no blank lines or comments. This module should include:

one function to parse the first line each block
one function to parse a single element mass fraction line in a block
one function to open the file and loop over the lines, calling the other functions

You should also write nose tests for each of the first two functions.

PROBLEM 7 Commit any necessary files to the repository and push this branch to github. Do not merge this into the master branch. Comments

It is convenient to be able to add comments to these files, but it will make it more complicated to read them.

PROBLEM 8 Create a branch from the matlib_basic branch called comments.

PROBLEM 9 Add the ability to recognize and ignore comments and blank lines at any point in the element library or material library files. You may want to create a module of utility functions that you can use in both of the previous modules to help.

Make your own simple element library and material library that includes the different conditions you would like to handle and write tests that confirm that your code works correctly.

PROBLEM 10 Commit any necessary files, including the simple library files you have generated, and push this branch to github. Do not merge this into any other branches. Expanding the Material Composition to a List of Nuclides

It is often useful to represent a material composition in terms of its nuclide abundances rather than its elemental mass fractions.

PROBLEM 11 Create a branch from the comments branch called expand_isos.

PROBLEM 12 Write a function that will take a single material as input and use the element library to generate a list of all the nuclides in that material and their isotopic abundances.

For nuclide, i, the atom density, N [mol/cc], can be determined by:

N_i = rho * w/o * a/o / MM

where:

rho is the mass density of the material
w/o is the mass fraction of the element in that material
a/o is the atom fraction of the isotope in that element
MM is the molar mass of that elemtn

To convert to the isotopic abundance of that nuclide, simply divide by the total atom density, summing over all the nuclides.

Your function should take a material data structure as input and return a single container that indicates the identity of each nuclide (Z & A) and its atomic abundance.

PROBLEM 13 Commit any necessary files, including testing files, and push this branch to github. Do not merge this into any other branches.