Encyclopedia API Tutorial
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    import requests
    import matplotlib.pyplot as plt
    # import json
    # import os

.. code:: ipython3

    # ENCYCLOPEDIA API URL
    nomad_api_url ="https://encyclopedia-api.nomad-coe.eu/v1.0/materials"

    # ENCYCLOPEDIA API Token (this one is valid for the NOMAD summer, no need to use a different one)
    api_access_token ="eyJpYXQiOjE1MDQ3MTg2NTAsImFsZyI6IkhTMjU2IiwiZXhwIjoxNTA3MzEwNjUwfQ.eyJpZCI6InRlc3RfdG9rZW4ifQ.hiCIfi0bAW_O6CsMpQaTBzqUhpfu6VguVEudm9HV7Xs"

    #### SEARCH EXAMPLES ###

    # search for a material by element, Exclusive ON
    # Note: this is the search used in order to get working the next steps for this tutorial. If you change
    # the search criteria then the rest of this tutorial should be changed as well (calc nr, material nr, ...)
    r = requests.post(nomad_api_url, auth=(api_access_token, ''), \
                      json = {"search_by":{"element": "Ag", "exclusive": "1"}})

    # search for materials by element, Exclusive OFF
    # r = requests.post(nomad_api_url, auth=(api_access_token, ''), \
    #                   json = {"search_by":{"element": "Ag", "exclusive": "0"}})

    # get the second page of previous results with 5 results per page
    # r = requests.post(nomad_api_url, auth=(api_access_token, ''), \
    #                   json = {"search_by":{"element": "Ag", "exclusive": "1", "page": 2, "per_page": 5}})

    # search for materials using multiple elements
    # r = requests.post(nomad_api_url, auth=(api_access_token, ''), \
    #                   json = {"search_by":{"element": "Ti,O", "exclusive": "1"}})

    # search for materials using formula
    # r = requests.post(nomad_api_url, auth=(api_access_token, ''), \
    #                   json = {"search_by":{"formula": "Ac2Ag3", "exclusive": "1"}})

    # search can be done also by using specific properties in combination with elements/formula
    # example: materials containing Ag and having DOS data
    # r = requests.post(nomad_api_url, auth=(api_access_token, ''), \
    #                   json = {"search_by":{"element": "Ag", "exclusive": "0"}, \
    #                          "has_dos": "True"})

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    # check the status code of the search command
    r.status_code

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    # check the results of our search
    content = r.json()

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    content

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    # get the total number of results
    content['total_results']

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    # check the number of results by counting the entries in "results" list
    len(content['results'])

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    # let's show the formula, reduced formula and the space_group for each material found
    for material in content['results']:
        print("formula:", material['formula'], "reduced formula:", material['formula_reduced'], "space_group: ", material['space_group'])

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    # let's create a list with the available materials id
    id_list =[]
    for material in content['results']:
        id_list.append(material['id'])
    print(id_list)

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    # get more properties for a specific material (for example: material_id 714)
    material_714 = requests.get(nomad_api_url + "/714", auth=(api_access_token, ''))

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    material_714.json()

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    # get all calculations for a specific material (material_id 714)
    material_714_calcs = requests.get("https://encyclopedia-api.nomad-coe.eu/v1.0/materials/714/calculations", auth=(api_access_token, ''))

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    # show the available calculations for our material
    calculations = material_714_calcs.json()
    calculations

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    # check how many calculations we have available for this specific material
    calculations['total_results']

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    # get the "id" and the "functional long name" property for the first calculation in our list
    calculations['results'][0]['id']
    calculations['results'][0]['functional_long_name']

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    # request a specific property for one calculation, here for example we ask for "density of states" data
    r = requests.get("https://encyclopedia-api.nomad-coe.eu/v1.0/materials/714/calculations/249502?property=dos", auth=(api_access_token, ''))

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    # it is good from time to time to check the status returned by our HTTP request :)
    r.status_code

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    # get only the DOS data from previous request result
    dos = r.json()

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    # show the DOS data
    dos

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    # let's see what kind of data we have there
    dos['dos'].keys()

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    # get only the DOS energies
    energies = dos['dos']['dos_energies']

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    # show the DOS energies
    energies

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    # get the DOS values
    values = dos['dos']['dos_values']

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    # show the DOS values
    values

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    type(values)

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    # show plots inline in notebook
    %matplotlib inline

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    # rescale the energy values by atomic unit of charge: 1.602176565e-19 (C)
    new_energy = [item/1.602176565e-19 for item in energies]

    # plotting things
    plt.plot(values[0], energies, color="darkorange", linewidth=1.5)