.. _quickstart:

==========
Quickstart
==========

Once Curie is installed (see :ref:`quickinstall`), everything is reached
through a single import::

	import curie as ci

This page maps out the toolkit — which class does what, and where to read
more — and gives a few short examples to run.

The Curie toolbox
-----------------

Curie's functionality lives in a handful of classes, grouped here by what
you would use them for.  The classes are designed to work together: peaks
fit from a spectrum feed a decay-chain fit, a foil's particle flux feeds a
cross-section average, and so on.

**Fitting gamma-ray spectra.**  `Spectrum` fits the peaks in HPGe
(high-purity germanium) detector data, using a `Calibration` (energy,
efficiency and resolution) and `Isotope` decay data to turn peak areas
into activities.  See :ref:`spectroscopy`.

**Production and decay calculations.**  `Isotope` provides decay data —
half-lives, decay radiations, dose rates — for a single nuclide, while
`DecayChain` solves the Bateman equations for a whole chain: forward
(predicting activities from a production rate) or inverse (fitting a
production rate or initial activity to measured decays, including peaks
read straight from a `Spectrum`).  See :ref:`isotopes`.

**Nuclear reaction data.**  `Reaction` gives a cross section as a function
of energy, with interpolation, flux-averaging and plotting; `Library`
searches the evaluated libraries (ENDF, TENDL, IRDFF, IAEA) for what is
available.  See :ref:`reactions`.

**Stopping powers and stacked targets.**  `Element` and `Compound` compute
charged-particle stopping powers, ranges and photon attenuation
coefficients; `Stack` transports a beam through a stack of foils to find
the particle energy in each — a flux that can be handed straight to
`Reaction.average`.  See :ref:`stopping`.

For the models and formulas behind these methods, see the
:ref:`methods` chapter; for every method and attribute, the :ref:`api`.

A few things to try
-------------------

The first two examples need no local files — Curie fetches the nuclear
data they use on first access.

Look up the decay data for a radionuclide::

	>>> ip = ci.Isotope('225RA')
	>>> print(ip.half_life('d'))
	14.9
	>>> print(ip.gammas())          # energies (keV) and intensities (%)
	   energy  intensity  unc_intensity
	0    40.0       30.0            1.5

Plot an evaluated reaction cross section (this one resolves to IRDFF-II)::

	rx = ci.Reaction('115IN(n,g)')  # neutron capture on 115In
	rx.plot(scale='loglog')

The third fits peaks in a real gamma-ray spectrum, so it needs a data
file.  Download ``eu_calib_7cm.Spe`` from the `examples directory`_ of the
repository and run from the folder you saved it in (or point the path at
your own ``.Spe``, ``.Chn``, ``.CNF`` or ``.IEC`` spectrum)::

	sp = ci.Spectrum('eu_calib_7cm.Spe')
	sp.isotopes = ['152EU']
	sp.plot()                       # the spectrum, with its fitted peaks

.. figure:: images/eu_spectrum_fit.png
   :width: 90%

   The fitted :sup:`152`\ Eu spectrum the code above produces.

Each links to a fuller, worked walk-through: :ref:`spectroscopy`,
:ref:`isotopes`, :ref:`reactions`.

.. _examples directory: https://github.com/jtmorrell/curie/tree/master/examples

Example scripts
---------------

Complete, runnable scripts covering each of these areas ship in the
`examples <https://github.com/jtmorrell/curie/tree/master/examples>`_
directory of the Curie repository, alongside the example data files they
use.

.. The shipped example scripts are intentionally minimal; expanding them
   into fuller, self-contained worked problems would strengthen this
   section.