.. DO NOT EDIT.
.. THIS FILE WAS AUTOMATICALLY GENERATED BY SPHINX-GALLERY.
.. TO MAKE CHANGES, EDIT THE SOURCE PYTHON FILE:
.. "auto_examples/05-counting/5.2-degradation-state.py"
.. LINE NUMBERS ARE GIVEN BELOW.

.. only:: html

    .. note::
        :class: sphx-glr-download-link-note

        :ref:`Go to the end <sphx_glr_download_auto_examples_05-counting_5.2-degradation-state.py>`
        to download the full example code.

.. rst-class:: sphx-glr-example-title

.. _sphx_glr_auto_examples_05-counting_5.2-degradation-state.py:


Compute the degradation state of a crater
=========================================

.. rubric:: By David Minton

In this example, we will emplace a small simple crater on a HiResLocal surface, and then apply topographic diffusion to the surface in order to simulate diffusive degradation of the crater. We will then compare the applied diffusive degradation amount with the estimated degradation state of the crater using the DepthCount model, which uses depth-to-diameter as a proxy for degradation state. If the proxy is good, the values of degradation state computed by Cratermaker vs applied degradation should plot along a 1:1 line.

.. GENERATED FROM PYTHON SOURCE LINES 9-67



.. image-sg:: /auto_examples/05-counting/images/sphx_glr_5.2-degradation-state_001.png
   :alt: 5.2 degradation state
   :srcset: /auto_examples/05-counting/images/sphx_glr_5.2-degradation-state_001.png
   :class: sphx-glr-single-img


.. rst-class:: sphx-glr-script-out

 .. code-block:: none

    Generating a new grid.
    Creating a new grid
    Center of local region: (0.0, 0.0)
    Radius of local region: 500.0 m
    Local region pixel size: 5.000 m
    Generated 30703 points in the local region.
    Generated 23717 points in the superdomain region.

    Queueing craters for emplacement:   0%|          | 0/1 [00:00<?, ?crater/s]
                                                                           

    Counting craters:   0%|          | 0/1 [00:00<?, ?craters/s]

                                                                





|

.. code-block:: Python


    from pathlib import Path

    import matplotlib.pyplot as plt
    import numpy as np

    from cratermaker import Simulation

    simdir = "simdata-5_2"

    # Note, that for these examples we pass ask_overwrite=False and reset=True to the Simulation constructor. This will suppress
    # prompts that ask the user if they want to overwrite existing files, which would would prevent these examples from running on their
    # own when building the documentation pages. Alternatively, calling cm.cleanup(simdir) will remove all pre-existing output files.

    sim = Simulation(
        surface="hireslocal",
        simdir=simdir,
        local_location=(0, 0),
        pix=5.0,
        local_radius=500.0,
        ask_overwrite=False,
        reset=True,
    )

    # Make a 100 m crater
    diameter = 100.0
    crater = sim.emplace(diameter=diameter, location=(0, 0))[0]
    K_func = sim.counting.measure_degradation_state

    # We'll use the crater's visibility function to help set the diffusion amount. We'll go to 1.5x the value of Kv
    niter = 10
    Kv = sim.counting.visibility_function(crater)
    K_max = 1.5 * Kv
    dK = K_max / niter

    sim.save()
    K_measured_vals = [K_func(crater)]
    K_applied_vals = [0.0]
    for K in np.linspace(dK, K_max, niter, endpoint=True):
        # Apply dK topographic diffusion to the surface
        sim.surface.local.apply_diffusion(dK)

        # Record what Cratermaker computes the degradation state to be
        K_measured_vals.append(K_func(crater))

        # Record what the degradation state ought to be
        K_applied_vals.append(K)

    # Normalize by radius^2 to make the plot unitless
    K_r2_measured = np.array(K_measured_vals) / crater.radius**2
    K_r2_applied = np.array(K_applied_vals) / crater.radius**2
    fig, ax = plt.subplots(layout="constrained")
    ax.scatter(K_r2_applied, K_r2_measured, label="Cratermaker simulation")
    ax.plot(K_r2_applied, K_r2_measured, color="k", linestyle="--", label="1:1")
    ax.set_xlabel("Applied diffusive degradation ($K/r^2)$")
    ax.set_ylabel("Estimated degradation state ($K/r^2$)")
    ax.legend()
    plt.show()


.. rst-class:: sphx-glr-timing

   **Total running time of the script:** (0 minutes 23.131 seconds)


.. _sphx_glr_download_auto_examples_05-counting_5.2-degradation-state.py:

.. only:: html

  .. container:: sphx-glr-footer sphx-glr-footer-example

    .. container:: sphx-glr-download sphx-glr-download-jupyter

      :download:`Download Jupyter notebook: 5.2-degradation-state.ipynb <5.2-degradation-state.ipynb>`

    .. container:: sphx-glr-download sphx-glr-download-python

      :download:`Download Python source code: 5.2-degradation-state.py <5.2-degradation-state.py>`

    .. container:: sphx-glr-download sphx-glr-download-zip

      :download:`Download zipped: 5.2-degradation-state.zip <5.2-degradation-state.zip>`


.. only:: html

 .. rst-class:: sphx-glr-signature

    `Gallery generated by Sphinx-Gallery <https://sphinx-gallery.github.io>`_