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# -*- coding: utf-8 -*-
'''
Defines parameters for simulation, used by example_parallel_network.py script

Copyright (C) 2018 Computational Neuroscience Group, NMBU.

This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.
'''
from __future__ import division
import matplotlib
import os
if not 'DISPLAY' in os.environ.keys():
    matplotlib.use('agg')
import os
import numpy as np
from scipy import stats
from glob import glob
import json
from parameters import ParameterSet
from mpi4py import MPI
import neuron
import sys
if sys.version < '3':
    stringType = 'S' # fix execution on Python 2 and 3
    from urllib2 import urlopen
else:
    stringType = 'U'
    from urllib.request import urlopen
from example_parallel_network_methods import get_templatename, get_params, get_syn_params
import LFPy

# set up MPI environment
COMM = MPI.COMM_WORLD
SIZE = COMM.Get_size()
RANK = COMM.Get_rank()


# load some neuron-interface files needed for the EPFL cell types
neuron.h.load_file("stdrun.hoc")
neuron.h.load_file("import3d.hoc")


#######################
# Functions
#######################
def get_pre_m_type(post):
    '''little helper function to return the most populuous excitatory m_type
    within the layer of m_type post, assuming this is representative for
    excitatory external connections onto postsynaptic cells '''
    if post.startswith('L23'):
        return 'L23_PC'
    elif post.startswith('L4'):
        return 'L4_PC'
    elif post.startswith('L5'):
        return 'L5_TTPC1'
    elif post.startswith('L6'):
        return 'L6_IPC'

#######################
# Parameters
#######################


# test mode (1 cell per pop, all-to-all connectivity)
TESTING = False

# Creating a NeuroTools.parameters.ParameterSet object for the main parameters
PSET = ParameterSet({})

# output file destination
if TESTING:
    PSET.OUTPUTPATH = 'example_parallel_network_output_testing'
else:
    PSET.OUTPUTPATH = 'example_parallel_network_output'

# input file paths
# PATHs to current cell-specific files and NMODL files
PSET.CWD = os.getcwd()
PSET.CELLPATH = 'hoc_combos_syn.1_0_10.allzips'
PSET.NMODL = 'hoc_combos_syn.1_0_10.allmods'


########################################################
# Simulation control
########################################################
PSET.dt = 2**-4             # simulation time step size (ms)
PSET.tstop = 1500.          # simulation duration (ms)
PSET.v_init = -77.          # membrane voltage(s) at t = 0 for all cells
PSET.celsius = 34.          # global temperature setting affecting active channels
PSET.TRANSIENT = 500.       # duration of startup transient

# population size scaling (multiplied with values in populationParams['POP_SIZE']):
PSET.POPSCALING = 1. 

# global scaling of connection probabilities (to counteract POPSCALING)
PSET.CONNPROBSCALING = 1. / PSET.POPSCALING

# switch for fully connected network (do not use with large population sizes)
PSET.fully_connected = True if TESTING else False

# bool flag switching LFP calculations on or off (faster)
PSET.COMPUTE_LFP = True

# bool flag switching ECoG calculation on or off
PSET.COMPUTE_ECOG = PSET.COMPUTE_LFP

# bool flag switching on calculations of electric current dipole moments per population
PSET.COMPUTE_P = PSET.COMPUTE_LFP

# bool flag switching on calculations of contributions to the extracellular
# potential per population
PSET.rec_pop_contributions = PSET.COMPUTE_LFP

# downsample factor for timeseries plots
PSET.decimate_q = 10

# settings for filtered signals shown in plots (fc=100 Hz, lowpass)
PSET.filterargs=dict(N=2, Wn=100.*2.*PSET.dt/1000*PSET.decimate_q, btype='lowpass')

# Base NetworkCell arguments, morphology and template specific args is
# defined below. 
cellParams = {
    'passive' :     False,
    'nsegs_method' : None,
    'v_init' : PSET.v_init,
    'tstart' : 0,
    'tstop' : PSET.tstop,
    'dt' : PSET.dt,
    'verbose' : False,
    'extracellular' : False,
    'delete_sections' : False,
}


#some stimuli to activate the network
PSET.PointProcParams = {
    'idx' : 0,
    'record_current' : False,
    'pptype' : 'IClamp',
    # 'amp' : 0.793, # amplitude parameter set later on
    'dur' : 1E6,
    'delay' : 0.,
}

# parameters for predicting extracellular potentials, specifying
# coordinates of electrodes and extracellular conductivity. So far only
# point contacts
PSET.electrodeParams = {
    'x' : np.zeros(16),
    'y' : np.zeros(16),
    'z' : np.linspace(-1500, 0, 16)[::-1],
    'sigma' : 0.3,
    'n' : 50,
    'N' : np.array([[0., 1., 0]]*16),
    'r' : 5.,
    'method' : 'soma_as_point',
}


# parameters for 4-sphere volume conductor model
# compute electrode positions on the outer radius for different angular offsets
_theta = np.linspace(-np.pi/4, np.pi / 4, 9)
_x = 90000.*np.sin(_theta)
_y = np.zeros(_theta.size)
_z = 90000.*np.cos(_theta)
PSET.foursphereParams = {
    'radii' : [79000., 80000., 85000., 90000.], # shell radii
    'sigmas' : [0.3, 1.5, 0.015, 0.3],          # shell conductivity
    'r' : np.c_[_x, _y, _z],                    # contact coordinates
}


# Optional arguments to Network.simulate() for computing extracellular potential
# contribution from passive leak, membrane capactitance and synaptic currents
PSET.NetworkSimulateArgs = {
    'use_ipas' : False,
    'use_icap' : False,
    'use_isyn' : False,
}

# layer thickness top to bottom L1-L6, Markram et al. 2015 Fig 3A. 
PSET.layer_data = np.array([('L1', 165., -82.5),
                            ('L2', 149., -239.5),
                            ('L3', 353., -490.5),
                            ('L4', 190., -762.),
                            ('L5', 525,  -1119.5),
                            ('L6', 700,  -1732.)],
    dtype=[('layer', '|{}2'.format(stringType)), ('thickness', float), ('center', float)])



# Define electrode geometry corresponding to an ECoG electrode, where contact
# points have a radius r, surface normal vectors N, and ECoG is calculated as the
# average LFP in n random points on each contact:
PSET.ecogParameters = {
    'sigma_S' : 0.,        # CSF conductivity            
    'sigma_T' : 0.3,        # GM conductivity
    'sigma_G' : 0.3,        # WM conductivity
    'h': PSET.layer_data['thickness'].sum(),
    'x' : np.array([0.]),    # x,y,z-coordinates of electrode contacts
    'y' : np.array([0.]),
    'z' : np.array([0.]),
    'z_shift' : -PSET.layer_data['thickness'].sum(), #+PSET.layer_data[4]['thickness']/8,
    'n' : 500,
    'r' : 250, # ECoG radii are often 500-1000 um
    'N' : np.array([[0., 0., 1.]]),
    'method': "pointsource",
}


# Main population parameters:
PSET.populationParameters = np.array([
        # Layer 4 
        # Excitatory
        ('L4_PC',       'cAD', 'L4_PC_cADpyr230_1',        2674,
         dict(radius=210, loc=PSET.layer_data[3]['center'], scale=100., cap=[1078., 97.]),
         dict(x=np.pi/2, y=0.), ['dend', 'apic'],            ['dend', 'apic'],   0.125,    5.),
        # Inhibitory
        ('L4_LBC',      'dNAC', 'L4_LBC_dNAC222_1',         122,
         dict(radius=210, loc=PSET.layer_data[3]['center'], scale=100., cap=[938., 670]),
         dict(x=np.pi/2, y=0.), ['soma', 'dend', 'apic'],    ['dend', 'apic'],   0.125,    5.),
        
        # Layer 5
        # Excitatory
        ('L5_TTPC1',    'cAD', 'L5_TTPC1_cADpyr232_1',     2403,
         dict(radius=210, loc=PSET.layer_data[4]['center'], scale=125., cap=[719, 73.]),
         dict(x=np.pi/2, y=0.), ['dend', 'apic'],            ['dend', 'apic'],   0.1,   5.),
        # Inhibitory
        ('L5_MC',       'bAC', 'L5_MC_bAC217_1',            395,
         dict(radius=210, loc=PSET.layer_data[4]['center'], scale=125., cap=[378., 890]),
         dict(x=np.pi/2, y=0.), ['soma', 'dend', 'apic'],    ['dend', 'apic'],   0.125,    5.),
        ],
    dtype = [('m_type', '|{}32'.format(stringType)), ('e_type', '|{}32'.format(stringType)),
             ('me_type', '|{}32'.format(stringType)), ('POP_SIZE', 'i8'), ('pop_args', dict),
             ('rotation_args', dict), ('syn_section', list),
             ('extrinsic_input_section', list), ('extrinsic_input_density', 'f8'),
             ('extrinsic_input_frequency', 'f8')])
# column data:
# shortnames as used in pathway_*.json files
# names as used to denote individual cell types
# POP_SIZE :    number of neurons for each morphological type as given on https://bbp.epfl.ch/nmc-portal/microcircuit 


# pop_args : dict, radius, mean position (loc) and standard deviation (scale) of the soma positions
# rotation_args : dict, default rotations around x and y axis applied to each cell in the population using LFPy.NetworkCell.set_rotation() method. 

# syn_section : list of section names where outgoing connections from this population are made onto postsynaptic neurons (i.e., no excitatory synapses on somatic sections anywhere)
# extrinsic_input_density : density of extrinisc incoming connections in units of [┬Ám^-2] 
# extrinsic_input_frequency : frequency of synapse activation in units of [Hz]

# TODO: Define only short names, pick random cell types or similar when creating populations. Column could be redone as [('m_type', '|U8'), ('e-type', '|U8')] and
# single cell objects picked from the glob('m+e type') on random

# # Override population sizes (for testing)
if TESTING:
    PSET.populationParameters['POP_SIZE'] = np.ones(PSET.populationParameters.size)


# Define a layer-specificity of connections L_YXL
# (see Hagen, Dahmen et al. (2016), Cereb Cortex) based on the anatomy of
# dendrites and axons. We here define this depth-dependence of synapse
# positioning as the product of total [soma + dendrite] length and
# total axon length in spatial bins corresponding to the thickness and
# boundaries of each layer. The products are normalized such that the sum of
# each column is 1, i.e., the sum of layer specificities of a connection
# between X and Y is 1.
PSET.L_YXL_m_types = {}
bins = np.r_[-PSET.layer_data['thickness'].cumsum()[::-1], 0]
for i, (y, Y, pop_args_Y, rotation_args_Y) in enumerate(zip(PSET.populationParameters['m_type'],
                                                            PSET.populationParameters['me_type'],
                                                            PSET.populationParameters['pop_args'],
                                                            PSET.populationParameters['rotation_args'])):
    # create a container for the layer specificities of connections
    data = np.zeros((PSET.layer_data.size,
                     PSET.populationParameters.size))
    
    # find and load the corresponding morphology files into LFPy
    m_Y = glob(os.path.join(PSET.CELLPATH, Y, 'morphology', '*.asc'))[0]
    cell_Y = LFPy.Cell(morphology=m_Y)
    cell_Y.set_rotation(**rotation_args_Y)
    cell_Y.set_pos(z=pop_args_Y['loc'])
    
    # sum the total length of axon in each layer bin
    layerbounds = np.r_[0, -PSET.layer_data['thickness'].cumsum()]
    len_Y_sum = np.zeros(PSET.layer_data.size)
    for k in range(PSET.layer_data.size):
        len_Y_sum[k] = cell_Y.length[cell_Y.get_idx(['soma', 'dend', 'apic'], z_min=layerbounds[k+1], z_max=layerbounds[k])].sum()
    for j, (X, pop_args_X, rotation_args_X) in enumerate(zip(PSET.populationParameters['me_type'],
                                                             PSET.populationParameters['pop_args'],
                                                             PSET.populationParameters['rotation_args'])):
        m_X = glob(os.path.join(PSET.CELLPATH, X, 'morphology', '*.asc'))[0]
        cell_X = LFPy.Cell(morphology=m_X)
        cell_X.set_rotation(**rotation_args_X)
        cell_X.set_pos(z=pop_args_X['loc'])
        
        len_X_sum = np.zeros(PSET.layer_data.size)
        for k in range(PSET.layer_data.size):
            len_X_sum[k] = cell_X.length[cell_X.get_idx('axon', z_min=layerbounds[k+1], z_max=layerbounds[k])].sum()
        
        data[:, j] = np.sqrt(len_Y_sum * len_X_sum) / np.sqrt(len_Y_sum * len_X_sum).sum()
    # fill in 
    PSET.L_YXL_m_types[y] = data
    
# clean up namespace
del cell_X, cell_Y, len_X_sum, len_Y_sum, data


# Container for LFPy.NetworkCell class parameters (path to morphology file etc.)
PSET.cellParameters = dict()

#################################################################################
# Set up various files and folders such that single-cell models from BBP can be used,
# and extract some numbers from pathway .json files
#################################################################################

# TODO: Add automated download of cell models from EPFL microcircuit portal


# autodownload some json files with anatomical and pathway specific data
pathway_files = ['pathways_anatomy_factsheets_simplified.json',
                 'pathways_physiology_factsheets_simplified.json']
if RANK == 0:
    for fname in pathway_files:            
        if not os.path.isfile(fname):
            u = urlopen('https://bbp.epfl.ch/nmc-portal/documents/10184/7288948/'+fname)
            localFile = open(fname, 'w')
            localFile.write(u.read().decode('utf-8'))
            localFile.close()
            u.close()
COMM.Barrier()

#flag for cell template file to switch on (inactive) synapses
add_synapses = False

# load synapse file info for each cell type as structured arrays in dictionary
synapses_tsv_dtype = [
    ('synapse_id', int),
    ('pre_cell_id', int),
    ('pre_mtype', int),
    ('sectionlist_id', int),
    ('sectionlist_index', int),
    ('seg_x', float),
    ('synapse_type', int),
    ('dep', float),
    ('fac', float),
    ('use', float),
    ('tau_d', float),
    ('delay', float),
    ('weight', float)
    ]
synapses_tsv = {}


# attempt to set up a folder with all unique EPFL mechanism mod files,
# compile, and load them all in order to be able to load cells as LFPy.NetworkCell objects 
if RANK == 0:
    if not os.path.isdir(PSET.NMODL):
        os.mkdir(PSET.NMODL)
        for NRN in PSET.populationParameters['me_type']:
            for nmodl in glob(os.path.join(PSET.CELLPATH, NRN, 'mechanisms', '*.mod')):
                while not os.path.isfile(os.path.join(PSET.NMODL,
                                                      os.path.split(nmodl)[-1])):
                    os.system('cp {} {}'.format(nmodl,
                                                os.path.join(PSET.NMODL,
                                                             '.')))
        os.chdir(PSET.NMODL)
        # patch faulty ProbGABAAB_EMS.mod file (otherwise stochastic inhibitory synapses will stay closed except at first activation)
        diff = '''319c319
<                 urand = scop_random(1)
---
>                 value = scop_random(1)
'''
        f = open('ProbGABAAB_EMS.patch', 'w')
        f.writelines(diff)
        f.close()
        os.system('patch ProbGABAAB_EMS.mod ProbGABAAB_EMS.patch')
        
        os.system('nrnivmodl')
        os.chdir(PSET.CWD)
COMM.Barrier()
neuron.load_mechanisms(PSET.NMODL)
os.chdir(PSET.CWD)


# Fill in dictionary of population-specific cell parameters
for NRN in PSET.populationParameters['me_type']:
    os.chdir(os.path.join(PSET.CWD, PSET.CELLPATH, NRN))
    
    #get the template name
    f = open("template.hoc", 'r')
    templatename = get_templatename(f)
    f.close()
    
    #get biophys template name
    f = open("biophysics.hoc", 'r')
    biophysics = get_templatename(f)
    f.close()
    
    #get morphology template name
    f = open("morphology.hoc", 'r')
    morphology = get_templatename(f)
    f.close()
    
    #get synapses template name
    f = open(os.path.join("synapses", "synapses.hoc"), 'r')
    synapses = get_templatename(f)
    f.close()

    if not hasattr(neuron.h, morphology): 
        """Create the cell model"""
        # Load morphology
        neuron.h.load_file(1, "morphology.hoc")
    if not hasattr(neuron.h, biophysics): 
        # Load biophysics
        neuron.h.load_file(1, "biophysics.hoc")
    if not hasattr(neuron.h, synapses):
        # load synapses
        neuron.h.load_file(1, os.path.join('synapses', 'synapses.hoc'))
    if not hasattr(neuron.h, templatename): 
        # Load main cell template
        neuron.h.load_file(1, "template.hoc")
    
    # create parameter dictionaries specific for each cell type (population)
    PSET.cellParameters[NRN] = dict(list(dict(
        morphology = glob(os.path.join('morphology', '*'))[0],
        templatefile = os.path.join(NRN, 'template.hoc'),
        templatename = templatename,
        templateargs=1 if add_synapses else 0,
        ).items()) + list(cellParams.items()))


# load synapse and connectivity data. mtype_map is the same for all cell types
if sys.version < '3':
    with open(os.path.join('synapses', 'mtype_map.tsv')) as f:
        mtype_map = np.loadtxt(f,
                               dtype={'names' : ('pre_mtype_id', 'pre_mtype'),
                                      'formats' : ('i4', '{}9'.format(stringType))},
                               converters = {1: lambda s: s.decode()})
else:
    with open(os.path.join('synapses', 'mtype_map.tsv'), encoding='us-ascii') as f:
        mtype_map = np.loadtxt(f, 
                               dtype={'names' : ('pre_mtype_id', 'pre_mtype'),
                                      'formats' : ('i4', '{}9'.format(stringType))},
                               converters = {1: lambda s: s.decode()})

os.chdir(PSET.CWD)


for name in PSET.populationParameters['m_type']:
    files = glob(os.path.join(PSET.CELLPATH, name+'*', 'synapses', 'synapses.tsv'))
    synapses_tsv[name] = np.array([], dtype=synapses_tsv_dtype)
    for f in files:
        synapses_tsv[name] = np.r_[synapses_tsv[name], np.loadtxt(f, dtype=synapses_tsv_dtype, skiprows = 1)]



# Open pathway anatomy and physiology factsheet files and read out info
pathways_anatomy = dict()
pathways_physiology = dict()

f = open(pathway_files[0], 'r')
j = json.load(f)
for pre in PSET.populationParameters['m_type']:
    for post in PSET.populationParameters['m_type']:
        key = '{}:{}'.format(pre, post)
        try:
            pathways_anatomy[key] = j[key]
        except KeyError:
            # fill in dummy data, no synapses will be created
            print('no pathway anatomy data for connection {}'.format(key))
            if sys.version < '3':
                pathways_anatomy[key] = {
                    'common_neighbor_bias': 0,
                    'connection_probability': 0,
                    'mean_number_of_synapse_per_connection': 0,
                    'number_of_convergent_neuron_mean': 0,
                    'number_of_convergent_neuron_std': 0,
                    'number_of_divergent_neuron_mean': 0,
                    'number_of_divergent_neuron_std': 0,
                    'number_of_synapse_per_connection_std': 0,
                    'total_synapse_count': 0,                    
                }            
            else:
                pathways_anatomy[key] = {
                    u'common_neighbor_bias': 0,
                    u'connection_probability': 0,
                    u'mean_number_of_synapse_per_connection': 0,
                    u'number_of_convergent_neuron_mean': 0,
                    u'number_of_convergent_neuron_std': 0,
                    u'number_of_divergent_neuron_mean': 0,
                    u'number_of_divergent_neuron_std': 0,
                    u'number_of_synapse_per_connection_std': 0,
                    u'total_synapse_count': 0,                    
                }
f.close()
j.clear()

f = open(pathway_files[1], 'r')
j = json.load(f)
for pre in PSET.populationParameters['m_type']:
    for post in PSET.populationParameters['m_type']:
        key = '{}:{}'.format(pre, post)
        try:
            pathways_physiology[key] = j[key]
        except KeyError:
            # fill in dummy data, no synapses will be created
            print('no pathway physiology data for connection {}'.format(key))
            if sys.version < '3':
                pathways_physiology[key] = {
                    'cv_psp_amplitude_mean': 3,
                    'cv_psp_amplitude_std': 0.95,
                    'd_mean': 360,
                    'd_std': 230,
                    'decay_mean': 9.8,
                    'decay_std': 6.7,
                    'epsp_mean': 1.6,
                    'epsp_std': 0.78,
                    'f_mean': 330,
                    'f_std': 240,
                    'failures_mean': 86,
                    'failures_std': 6.5,
                    'gsyn_mean': 0.3,
                    'gsyn_std': 0.11,
                    'latency_mean': 0.33,
                    'latency_std': 0.18,
                    'risetime_mean': 0.43,
                    'risetime_std': 0.47,
                    'space_clamp_correction_factor': 3.6,
                    'synapse_type': u'Excitatory, depressing',
                    'u_mean': 0.19,
                    'u_std': 0.23
                }            
            else:
                pathways_physiology[key] = {
                    u'cv_psp_amplitude_mean': 3,
                    u'cv_psp_amplitude_std': 0.95,
                    u'd_mean': 360,
                    u'd_std': 230,
                    u'decay_mean': 9.8,
                    u'decay_std': 6.7,
                    u'epsp_mean': 1.6,
                    u'epsp_std': 0.78,
                    u'f_mean': 330,
                    u'f_std': 240,
                    u'failures_mean': 86,
                    u'failures_std': 6.5,
                    u'gsyn_mean': 0.3,
                    u'gsyn_std': 0.11,
                    u'latency_mean': 0.33,
                    u'latency_std': 0.18,
                    u'risetime_mean': 0.43,
                    u'risetime_std': 0.47,
                    u'space_clamp_correction_factor': 3.6,
                    u'synapse_type': u'Excitatory, depressing',
                    u'u_mean': 0.19,
                    u'u_std': 0.23
                }
f.close()
j.clear()


# get out stats for synapses and connections, temporary
syn_param_stats = get_syn_params(PSET.populationParameters['m_type'],
                                 PSET.populationParameters['me_type'],
                                 pathways_physiology, mtype_map, synapses_tsv)

del synapses_tsv # not needed anymore. 


###########################################################################
# Set up main connection parameters used by Network class instance methods
############################################################################

# Main connection parameters between pre and post-synaptic populations organized as
# dictionary of parameter lists between pre and postsynaptic populations:
if PSET.fully_connected:
    connprob = [[1]*PSET.populationParameters.size]*PSET.populationParameters.size # fully connected network (no selfconnections)
else:
    connprob = get_params(PSET.populationParameters['m_type'], pathways_anatomy,
                          'connection_probability', 0.01*PSET.CONNPROBSCALING)  #unit conversion % -> fraction, increase weight  ewith diluted network

PSET.connParams = dict(
    # connection probabilities between populations    
    connprob = connprob,
    
    # synapse mechanisms
    syntypes = [[neuron.h.ProbAMPANMDA_EMS
                 if syn_param_stats['{}:{}'.format(pre, post)]['synapse_type'] >= 100 else
                 neuron.h.ProbGABAAB_EMS for post in PSET.populationParameters['m_type']] for pre in PSET.populationParameters['m_type']],
    
    
    # synapse time constants and reversal potentials.
    # Use the mean/global EPFL synapse model parameters
    # (for now) as some connections appear to be missing in pathway files.
    synparams = [[  dict(
                        Use = syn_param_stats['{}:{}'.format(pre, post)]['Use_mean'],
                        Dep = syn_param_stats['{}:{}'.format(pre, post)]['Dep_mean'],
                        Fac = syn_param_stats['{}:{}'.format(pre, post)]['Fac_mean'],
                        tau_r_AMPA = 0.2,
                        tau_d_AMPA = syn_param_stats['{}:{}'.format(pre, post)]['tau_d_mean'],
                        tau_r_NMDA = 0.29,
                        tau_d_NMDA = 43,
                        e=0,
                        mg=1,
                        u0=0,
                        synapseID=0,
                        verboseLevel=0,
                        NMDA_ratio=0.4 # this may take on several values in synconf.txt files, not acccounted for here
                    )
                if syn_param_stats['{}:{}'.format(pre, post)]['synapse_type'] >= 100 else
                    dict(
                        Use = syn_param_stats['{}:{}'.format(pre, post)]['Use_mean'],
                        Dep = syn_param_stats['{}:{}'.format(pre, post)]['Dep_mean'],
                        Fac = syn_param_stats['{}:{}'.format(pre, post)]['Fac_mean'],
                        tau_r_GABAA = 0.2, #from synapses.hoc: rng.lognormal(0.2, 0.1) (mean, variance)
                        tau_d_GABAA = syn_param_stats['{}:{}'.format(pre, post)]['tau_d_mean'],
                        tau_r_GABAB = 3.5,
                        tau_d_GABAB = 260.9,
                        e_GABAA = -80,
                        e_GABAB = -75.8354,
                        u0 = 0,
                        synapseID = 0,
                        verboseLevel = 0,
                        GABAB_ratio = 0.0, # this may take on several values, in synconf.txt files, not acccounted for here
                    )
                for post in PSET.populationParameters['m_type']] for pre in PSET.populationParameters['m_type']],

    # maximum conductances
    weightfuns = [[np.random.normal]*PSET.populationParameters.size]*PSET.populationParameters.size,
    weightargs = get_params(PSET.populationParameters['m_type'], pathways_physiology,
                            ['gsyn_mean', 'gsyn_std'], 1.),
    # Correct??? (very small PSPs otherwise).
    # Also, weights in unknown units loaded from synapses_tsv is different than the reported averaged gsyn. 
    
    # connection delays
    delayfuns = [[np.random.normal]*PSET.populationParameters.size]*PSET.populationParameters.size,
    delayargs = [[dict(
            loc=syn_param_stats['{}:{}'.format(pre, post)]['delay_mean'],
            scale=syn_param_stats['{}:{}'.format(pre, post)]['delay_std']
        ) for post in PSET.populationParameters['m_type']] for pre in PSET.populationParameters['m_type']],
    
    
    # numbers of synapses per connection
    multapsefuns = [[np.random.normal]*PSET.populationParameters.size]*PSET.populationParameters.size,
    multapseargs = get_params(PSET.populationParameters['m_type'], pathways_anatomy,
                              ['mean_number_of_synapse_per_connection',
                               'number_of_synapse_per_connection_std']),
    
    # parameters for finding random synapse locations using the method
    # LFPy.Cell.get_rand_idx_area_and_distribution_norm. The argument nidx is default to 1
    syn_pos_args = [[dict(section=syn_section,
                          z_min=-1E6,
                          z_max=1E6,
                          fun=[stats.norm]*PSET.layer_data.size,
                          funargs=[dict(loc=loc, scale=scale/2.) for loc, scale in PSET.layer_data[['center', 'thickness']]],
                          funweights=PSET.L_YXL_m_types[post_m_type][:, i]
                          ) for i, pre_m_type in enumerate(PSET.populationParameters['m_type'])] for post_m_type, syn_section in PSET.populationParameters[['m_type', 'syn_section']]],   
)

# save connection data
PSET.save_connections = True

# connection parameters for synapses activated by putative external population(s)
PSET.connParamsExtrinsic = dict(
    # synapse type
    syntype = 'ProbAMPANMDA_EMS',
    # synapse parameters (assumes parameters of excitatory population in the layer)
    synparams = [dict(
                        Use = syn_param_stats['{}:{}'.format(get_pre_m_type(post), post)]['Use_mean'],
                        Dep = syn_param_stats['{}:{}'.format(get_pre_m_type(post), post)]['Dep_mean'],
                        Fac = syn_param_stats['{}:{}'.format(get_pre_m_type(post), post)]['Fac_mean'],
                        tau_r_AMPA = 0.2,
                        tau_d_AMPA = syn_param_stats['{}:{}'.format(get_pre_m_type(post), post)]['tau_d_mean'],
                        tau_r_NMDA = 0.29,
                        tau_d_NMDA = 43,
                        e=0,
                        mg=1,
                        u0=0,
                        synapseID=0,
                        verboseLevel=0,
                        NMDA_ratio=0.4 # this may take on several values in synconf.txt files, not acccounted for here        
    ) for post in PSET.populationParameters['m_type']],

    # maximum conductances
    weightfuns = [np.random.normal]*PSET.populationParameters.size,
    weightargs = [get_params(np.array([m_type]), pathways_physiology,
                        ['gsyn_mean', 'gsyn_std'], 1.)[0][0] for m_type in PSET.populationParameters['m_type']],
)