.. currentmodule:: brian2

.. cuba_openmp:

Example: cuba_openmp
====================


        .. only:: html

            .. |launchbinder| image:: file:///usr/share/doc/python-brian-doc/docs/badge.svg
            .. _launchbinder: https://mybinder.org/v2/gh/brian-team/brian2-binder/master?filepath=examples/standalone/cuba_openmp.ipynb

            .. note::
               You can launch an interactive, editable version of this
               example without installing any local files
               using the Binder service (although note that at some times this
               may be slow or fail to open): |launchbinder|_

        

Run the ``cuba.py`` example with OpenMP threads.

::

    from brian2 import *
    
    set_device('cpp_standalone', directory='CUBA')
    prefs.devices.cpp_standalone.openmp_threads = 4
    
    taum = 20*ms
    taue = 5*ms
    taui = 10*ms
    Vt = -50*mV
    Vr = -60*mV
    El = -49*mV
    
    eqs = '''
    dv/dt  = (ge+gi-(v-El))/taum : volt (unless refractory)
    dge/dt = -ge/taue : volt (unless refractory)
    dgi/dt = -gi/taui : volt (unless refractory)
    '''
    
    P = NeuronGroup(4000, eqs, threshold='v>Vt', reset='v = Vr', refractory=5*ms,
                    method='exact')
    P.v = 'Vr + rand() * (Vt - Vr)'
    P.ge = 0*mV
    P.gi = 0*mV
    
    we = (60*0.27/10)*mV # excitatory synaptic weight (voltage)
    wi = (-20*4.5/10)*mV # inhibitory synaptic weight
    Ce = Synapses(P, P, on_pre='ge += we')
    Ci = Synapses(P, P, on_pre='gi += wi')
    Ce.connect('i<3200', p=0.02)
    Ci.connect('i>=3200', p=0.02)
    
    s_mon = SpikeMonitor(P)
    
    run(1 * second)
    
    plot(s_mon.t/ms, s_mon.i, ',k')
    xlabel('Time (ms)')
    ylabel('Neuron index')
    show()
    

