.. tutorial

Current Examples
=========================================


This demo is implemented in a single Python file. Download here: :download:`tutorial_current.ipynb`

This demo illustrates how to:

* Define currents in the electrodes.

::

    from module1_mesh import*
    from module2_forward import*
    from module3_inverse import*
    from module4_auxiliar import*
    import matplotlib.pyplot as plt
    %matplotlib inline


Mesh
**********************

::

  "Electrodes and Mesh"
    ele_pos=electrodes_position(L=6, per_cober=0.5, rotate=0)
    mesh_direct=MyMesh(r=1, n=20, n_in=40, n_out=8, electrodes_obj=ele_pos)
    plot(mesh_direct);

.. image:: current/mesh.png
   :scale: 75 %

Defining Gamma function
****************************************

::

    "Gamma function"
    ValuesCells0=GammaCircle(mesh_direct,3.0,1.0,0.50, 0.25, 0.25);
    gamma0=CellFunction(mesh_direct, values=ValuesCells0)

    "Plot"
    V_DG=FiniteElement('DG',mesh_direct.ufl_cell(),0)
    gamma_direct=plot_figure(mesh_direct, V_DG, gamma0, name="Gamma");
    
.. image:: current/gamma.png
   :scale: 75 %


Forward Problem
****************************************

::

    "Forward Problem"
    VD=FiniteElement('CG',mesh_direct.ufl_cell(),1) #Lagrange pol. degree 1
    L=ele_pos.L
    l=int(L)                                        #Measurements number.
    z=np.ones(L)*0.025                              #Impedance

    #Solver
    ForwardObject=ForwardProblem(mesh_direct, z)

Current Examples
****************************************


Method 1
----------------------
::

    >>> I_all=current_method(L,l, method=1)           
    >>> list_u0, list_U0 = ForwardObject.solve_forward(VD, I_all, gamma0)

    This method only accept until L/2 currents, returning L/2 currents.
    
::
    
    >>> print(np.array(I_all))
    [[ 1.  0.  0. -1.  0.  0.]
     [ 0.  1.  0.  0. -1.  0.]
     [ 0.  0.  1.  0.  0. -1.]]
    
::
    
    plt.figure(figsize=(10, 10))
    for i in range(0, int(l/2)):
        plt.subplot(4,4,i+1)
        plot(list_u0[i])

.. image:: current/method1.png
   :scale: 75 %


Method 2
----------------------
::

    >>> I_all=current_method(L,l, method=2)           
    >>> list_u0, list_U0 = ForwardObject.solve_forward(VD, I_all, gamma0)

::
    
    >>> print(np.array(I_all))
    [[ 1. -1.  0.  0.  0.  0.]
     [ 0.  1. -1.  0.  0.  0.]
     [ 0.  0.  1. -1.  0.  0.]
     [ 0.  0.  0.  1. -1.  0.]
     [ 0.  0.  0.  0.  1. -1.]
     [ 1.  0.  0.  0.  0. -1.]]
     
::

    plt.figure(figsize=(10, 10))
    for i in range(0, int(l)):
        plt.subplot(4,4,i+1)
        plot(list_u0[i])

.. image:: current/method2.png
   :scale: 75 %

Method 3
----------------------
::

    >>> I_all=current_method(L,l, method=3)           
    >>> list_u0, list_U0 = ForwardObject.solve_forward(VD, I_all, gamma0)

::

        >>> np.set_printoptions(precision=5)
        >>> print(np.array(I_all))
        [[ 1.  -0.2 -0.2 -0.2 -0.2 -0.2]
         [-0.2  1.  -0.2 -0.2 -0.2 -0.2]
         [-0.2 -0.2  1.  -0.2 -0.2 -0.2]
         [-0.2 -0.2 -0.2  1.  -0.2 -0.2]
         [-0.2 -0.2 -0.2 -0.2  1.  -0.2]
         [-0.2 -0.2 -0.2 -0.2 -0.2  1. ]]

::

        plt.figure(figsize=(10, 10))
        for i in range(0, int(l)):
            plt.subplot(4,4,i+1)
            plot(list_u0[i])

.. image:: current/method3.png
   :scale: 75 %


Method 4
----------------------
::

    >>> I_all=current_method(L,l, method=4)           
    >>> list_u0, list_U0 = ForwardObject.solve_forward(VD, I_all, gamma0)

::

        >>> np.set_printoptions(precision=1)
        >>> print(np.array(I_all))
        [[ 8.7e-01  8.7e-01  1.2e-16 -8.7e-01 -8.7e-01 -2.4e-16]
         [ 8.7e-01 -8.7e-01 -2.4e-16  8.7e-01 -8.7e-01 -4.9e-16]
         [ 1.2e-16 -2.4e-16  3.7e-16 -4.9e-16  2.4e-15 -7.3e-16]
         [-8.7e-01  8.7e-01 -4.9e-16 -8.7e-01  8.7e-01 -9.8e-16]
         [-8.7e-01 -8.7e-01  2.4e-15  8.7e-01  8.7e-01 -4.8e-15]
         [-2.4e-16 -4.9e-16 -7.3e-16 -9.8e-16 -4.8e-15 -1.5e-15]]

::

        plt.figure(figsize=(10, 10))
        for i in range(0, int(l)):
            plt.subplot(4,4,i+1)
            plot(list_u0[i])

.. image:: current/method4.png
   :scale: 75 %
   

Setting Diffent Values
----------------------
::

    I_all=current_method(L,l, method=2, value=1.337)
    np.set_printoptions(precision=4)

::

    >>> print(np.array(I_all))
    [[ 1.337 -1.337  0.     0.     0.     0.   ]
     [ 0.     1.337 -1.337  0.     0.     0.   ]
     [ 0.     0.     1.337 -1.337  0.     0.   ]
     [ 0.     0.     0.     1.337 -1.337  0.   ]
     [ 0.     0.     0.     0.     1.337 -1.337]
     [ 1.337  0.     0.     0.     0.    -1.337]]

::

    I_all=current_method(L,l, method=3, value=1.337)
    np.set_printoptions(precision=4)

::

    >>> print(np.array(I_all))
    [[ 1.337  -0.2674 -0.2674 -0.2674 -0.2674 -0.2674]
     [-0.2674  1.337  -0.2674 -0.2674 -0.2674 -0.2674]
     [-0.2674 -0.2674  1.337  -0.2674 -0.2674 -0.2674]
     [-0.2674 -0.2674 -0.2674  1.337  -0.2674 -0.2674]
     [-0.2674 -0.2674 -0.2674 -0.2674  1.337  -0.2674]
     [-0.2674 -0.2674 -0.2674 -0.2674 -0.2674  1.337 ]]



My Current
----------------------
::

    I_all= [ [5, -3, -1, 1, -2, 0],
             [1, 1, -1, -1, 0, 0],
             [8.5, 0, -3.5,0 ,0, -3]]
    l=len(I_all)

    list_u0, list_U0 = ForwardObject.solve_forward(VD, I_all, gamma0)
    
::
    
    plt.figure(figsize=(10, 10))
    for i in range(0, l):
        plt.subplot(4,4,i+1)
        plot(list_u0[i])

.. image:: current/mycurrent.png
   :scale: 75 %