#!/usr/bin/env python
# coding: utf-8

# # Micromagnetic model
# 
# ## Mesh

# In[1]:


import oommfc as oc


# In[2]:


get_ipython().run_line_magic('matplotlib', 'inline')
L = 100e-9
d = 10e-9
mesh = oc.Mesh(p1=(0, 0, 0), p2=(L, L, L), cell=(d, d, d), name="mesh")
mesh


# The domain edge lengths in x, y, and z directions are:

# In[3]:


mesh.l


# The number of cells in all three directions:

# In[4]:


mesh.n


# The centre point of the mesh:

# In[5]:


mesh.centre


# ## System

# The basic block of our micromagnetic model is the system object. It is fully defined if:
# 
# 1. Hamiltonian,
# 2. dynamics equation,
# 3. magnetisation.
# 
# are provided. The system is then "driven" in phase space using particular drivers.

# In[6]:


system = oc.System(name="system")


# ## Hamiltonian

# In[7]:


exchange = oc.Exchange(A=1e-12)


# In[8]:


exchange


# In[9]:


exchange.A


# In[10]:


repr(exchange)


# In[11]:


hamiltonian = exchange + oc.Zeeman(H=(1e6, 0, 0))

type(hamiltonian)


# In[12]:


system.hamiltonian = hamiltonian


# In[13]:


system.hamiltonian


# In[14]:


system.hamiltonian.exchange.A


# In[15]:


system.hamiltonian.zeeman.H


# In[16]:


system.hamiltonian += oc.Demag(name="energy_term_name")


# In[17]:


system.hamiltonian.energy_term_name


# ## Dynamics

# In[18]:


system.dynamics = oc.Precession(gamma=2.211e5) + oc.Damping(alpha=0.1)


# In[19]:


system.dynamics


# ## Magnetisation

# In[20]:


import discretisedfield as df


# In[21]:


Ms = 8e5
m = df.Field(mesh, value=(1, 0, 1), norm=Ms, name="m")


# In[22]:


p = (50e-9, 50e-9, 5e-9)
m(p)  # sampling


# In[23]:


m.f = lambda pos: (pos[0]+pos[2]+1, pos[2], 0)


# In[24]:


system.m = m


# ## Drivers

# ### MinDriver

# In[25]:


md = oc.MinDriver()
md.drive(system)


# In[26]:


system.m.average


# In[27]:


system.m.plot_plane("z")


# In[28]:


system.hamiltonian.zeeman.H = (0, 1e7, 0)


# In[29]:


md.drive(system)


# In[30]:


system.m.plot_plane("z")


# ### Time driver

# In[31]:


system.hamiltonian += oc.UniaxialAnisotropy(K1=5e3, u=(0, 0, 1))
system.hamiltonian.zeeman.H = (1e6, 0, 0)


# In[32]:


td = oc.TimeDriver()
td.drive(system, t=0.2e-9, n=50)


# In[33]:


system.m.plot_plane("z")


# In[34]:


system.dt


# In[35]:


system.dt.plot("t", "E")