| 1 | : Based on: |
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| 2 | : $Id$ |
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| 3 | : but with fixed duration rather than fixed number of spikes, and an interval |
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| 4 | : that can safely be varied during the simulation |
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| 5 | : Modified by Andrew Davison, UNIC, CNRS |
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| 6 | |
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| 7 | NEURON { |
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| 8 | ARTIFICIAL_CELL NetStimFD |
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| 9 | RANGE interval, start, duration |
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| 10 | RANGE noise |
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| 11 | THREADSAFE : only true if every instance has its own distinct Random |
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| 12 | POINTER donotuse |
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| 13 | } |
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| 14 | |
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| 15 | PARAMETER { |
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| 16 | interval = 10 (ms) <1e-9,1e9> : time between spikes (msec) |
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| 17 | duration = 100 (ms) <0,1e9> : duration of firing (msec) |
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| 18 | start = 50 (ms) : start of first spike |
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| 19 | noise = 0 <0,1> : amount of randomness (0.0 - 1.0) |
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| 20 | } |
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| 21 | |
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| 22 | ASSIGNED { |
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| 23 | event (ms) |
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| 24 | on |
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| 25 | donotuse |
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| 26 | valid |
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| 27 | } |
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| 28 | |
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| 29 | PROCEDURE seed(x) { |
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| 30 | set_seed(x) |
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| 31 | } |
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| 32 | |
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| 33 | INITIAL { |
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| 34 | valid = 4 |
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| 35 | on = 0 : off |
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| 36 | if (noise < 0) { |
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| 37 | noise = 0 |
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| 38 | } |
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| 39 | if (noise > 1) { |
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| 40 | noise = 1 |
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| 41 | } |
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| 42 | if (start >= 0 && duration > 0) { |
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| 43 | : randomize the first spike so on average it occurs at |
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| 44 | : start + noise*interval |
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| 45 | invl(interval) : for some reason, the first invl() call seems to give implausibly large values, so we discard it |
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| 46 | event = start + invl(interval) - interval*(1. - noise) |
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| 47 | : but not earlier than 0 |
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| 48 | if (event < 0) { |
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| 49 | event = 0 |
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| 50 | } |
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| 51 | if (event < start+duration) { |
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| 52 | on = 1 |
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| 53 | net_send(event, 3) |
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| 54 | } |
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| 55 | } |
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| 56 | } |
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| 57 | |
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| 58 | PROCEDURE init_sequence(t(ms)) { |
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| 59 | if (duration > 0) { |
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| 60 | on = 1 |
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| 61 | event = 0 |
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| 62 | } |
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| 63 | } |
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| 64 | |
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| 65 | FUNCTION invl(mean (ms)) (ms) { |
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| 66 | if (mean <= 0.0) { |
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| 67 | mean = 0.01 (ms) : I would worry if it were 0.0 |
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| 68 | } |
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| 69 | if (noise == 0) { |
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| 70 | invl = mean |
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| 71 | }else{ |
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| 72 | invl = (1.0 - noise)*mean + noise*mean*erand() |
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| 73 | } |
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| 74 | } |
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| 75 | VERBATIM |
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| 76 | double nrn_random_pick(void* r); |
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| 77 | void* nrn_random_arg(int argpos); |
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| 78 | ENDVERBATIM |
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| 79 | |
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| 80 | FUNCTION erand() { |
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| 81 | VERBATIM |
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| 82 | if (_p_donotuse) { |
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| 83 | /* |
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| 84 | :Supports separate independent but reproducible streams for |
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| 85 | : each instance. However, the corresponding hoc Random |
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| 86 | : distribution MUST be set to Random.negexp(1) |
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| 87 | */ |
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| 88 | _lerand = nrn_random_pick(_p_donotuse); |
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| 89 | }else{ |
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| 90 | /* only can be used in main thread */ |
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| 91 | if (_nt != nrn_threads) { |
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| 92 | hoc_execerror("multithread random in NetStim"," only via hoc Random"); |
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| 93 | } |
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| 94 | ENDVERBATIM |
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| 95 | : the old standby. Cannot use if reproducible parallel sim |
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| 96 | : independent of nhost or which host this instance is on |
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| 97 | : is desired, since each instance on this cpu draws from |
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| 98 | : the same stream |
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| 99 | erand = exprand(1) |
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| 100 | VERBATIM |
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| 101 | } |
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| 102 | ENDVERBATIM |
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| 103 | } |
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| 104 | |
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| 105 | PROCEDURE noiseFromRandom() { |
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| 106 | VERBATIM |
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| 107 | { |
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| 108 | void** pv = (void**)(&_p_donotuse); |
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| 109 | if (ifarg(1)) { |
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| 110 | *pv = nrn_random_arg(1); |
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| 111 | }else{ |
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| 112 | *pv = (void*)0; |
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| 113 | } |
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| 114 | } |
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| 115 | ENDVERBATIM |
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| 116 | } |
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| 117 | |
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| 118 | PROCEDURE next_invl() { |
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| 119 | if (duration > 0) { |
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| 120 | event = invl(interval) |
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| 121 | } |
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| 122 | if (t+event >= start+duration) { |
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| 123 | on = 0 |
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| 124 | } |
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| 125 | :printf("t=%g, event=%g, t+event=%g, on=%g\n", t, event, t+event, on) |
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| 126 | } |
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| 127 | |
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| 128 | NET_RECEIVE (w) { |
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| 129 | if (flag == 0) { : external event |
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| 130 | :printf("external event. w = %g\n", w) |
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| 131 | if (w > 0) { : turn on spike sequence |
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| 132 | : but not if a netsend is on the queue |
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| 133 | init_sequence(t) |
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| 134 | : randomize the first spike so on average it occurs at |
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| 135 | : noise*interval (most likely interval is always 0) |
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| 136 | next_invl() |
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| 137 | event = event - interval*(1.0 - noise) |
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| 138 | valid = valid + 1 : events with previous values of valid will be ignored. |
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| 139 | net_send(event, valid) |
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| 140 | }else if (w < 0) { : turn off spiking definitively |
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| 141 | on = 0 |
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| 142 | } |
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| 143 | } |
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| 144 | if (flag == 3) { : from INITIAL |
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| 145 | if (on == 1) { : but ignore if turned off by external event |
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| 146 | init_sequence(t) |
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| 147 | net_send(0, valid) |
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| 148 | :printf("init_sequence(%g)\n", t) |
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| 149 | } |
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| 150 | } |
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| 151 | if (flag == valid && on == 1) { |
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| 152 | net_event(t) |
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| 153 | next_invl() |
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| 154 | :printf("%g %g %g flag=%g valid=%g\n", t, interval, event, flag, valid) |
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| 155 | if (on == 1) { |
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| 156 | net_send(event, valid) |
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| 157 | } |
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| 158 | } |
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| 159 | } |
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| 160 | |
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| 161 | COMMENT |
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| 162 | Presynaptic spike generator |
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| 163 | --------------------------- |
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| 164 | |
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| 165 | This mechanism has been written to be able to use synapses in a single |
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| 166 | neuron receiving various types of presynaptic trains. This is a "fake" |
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| 167 | presynaptic compartment containing a spike generator. The trains |
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| 168 | of spikes can be either periodic or noisy (Poisson-distributed) |
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| 169 | |
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| 170 | Parameters; |
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| 171 | noise: between 0 (no noise-periodic) and 1 (fully noisy) |
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| 172 | interval: mean time between spikes (ms) |
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| 173 | [number: number of spikes (independent of noise)] - deleted |
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| 174 | duration: duration of spiking (ms) - added |
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| 175 | |
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| 176 | Written by Z. Mainen, modified by A. Destexhe, The Salk Institute |
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| 177 | |
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| 178 | Modified by Michael Hines for use with CVode |
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| 179 | The intrinsic bursting parameters have been removed since |
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| 180 | generators can stimulate other generators to create complicated bursting |
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| 181 | patterns with independent statistics (see below) |
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| 182 | |
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| 183 | Modified by Michael Hines to use logical event style with NET_RECEIVE |
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| 184 | This stimulator can also be triggered by an input event. |
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| 185 | If the stimulator is in the on==0 state (no net_send events on queue) |
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| 186 | and receives a positive weight |
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| 187 | event, then the stimulator changes to the on=1 state and goes through |
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| 188 | its entire spike sequence before changing to the on=0 state. During |
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| 189 | that time it ignores any positive weight events. If, in an on!=0 state, |
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| 190 | the stimulator receives a negative weight event, the stimulator will |
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| 191 | change to the on==0 state. In the on==0 state, it will ignore any ariving |
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| 192 | net_send events. A change to the on==1 state immediately fires the first spike of |
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| 193 | its sequence. |
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| 194 | |
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| 195 | ENDCOMMENT |
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| 196 | |
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