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Merge remote-tracking branch 'upstream/master'

1 files changed, 228 insertions, 0 deletions

diff --git a/nn/layer_dag.lua b/nn/layer_dag.lua
new file mode 100644
index 0000000..1ab18fa
--- /dev/null
+++ b/nn/layer_dag.lua
@@ -0,0 +1,228 @@
+local DAGLayer = nerv.class("nerv.DAGLayer", "nerv.Layer")
+
+local function parse_id(str)
+    local id, port, _
+    _, _, id, port = string.find(str, "([a-zA-Z0-9_]+)%[([0-9]+)%]")
+    if id == nil or port == nil then
+        _, _, id, port = string.find(str, "(.+)%[([0-9]+)%]")
+        if not (id == "<input>" or id == "<output>") then
+            nerv.error("wrong format of connection id")
+        end
+    end
+    port = tonumber(port)
+    return id, port
+end
+
+local function discover(id, layers, layer_repo)
+    local ref = layers[id]
+    if id == "<input>" or id == "<output>" then
+        return nil
+    end
+    if ref == nil then
+        local layer = layer_repo:get_layer(id)
+        local dim_in, dim_out = layer:get_dim()
+        ref = {
+            layer = layer,
+            inputs = {},
+            outputs = {},
+            err_inputs = {},
+            err_outputs = {},
+            next_layers = {},
+            input_len = #dim_in,
+            output_len = #dim_out,
+            in_deg = 0,
+            visited = false
+        }
+        layers[id] = ref
+    end
+    return ref
+end
+
+function nerv.DAGLayer:__init(id, global_conf, layer_conf)
+    local layers = {}
+    local inputs = {}
+    local outputs = {}
+    local dim_in = layer_conf.dim_in
+    local dim_out = layer_conf.dim_out
+    for from, to in pairs(layer_conf.connections) do
+        local id_from, port_from = parse_id(from)
+        local id_to, port_to = parse_id(to)
+        local ref_from = discover(id_from, layers, layer_conf.sub_layers)
+        local ref_to = discover(id_to, layers, layer_conf.sub_layers)
+        local input_dim, output_dim, _
+        if ref_from and ref_from.outputs[port_from] ~= nil then
+            nerv.error("%s has already been attached", from)
+        end
+        if ref_to and ref_to.inputs[port_to] ~= nil then
+            nerv.error("%s has already been attached", to)
+        end
+        if id_from == "<input>" then
+            input_dim, _ = ref_to.layer:get_dim()
+            if dim_in[port_from] ~= input_dim[port_to] then
+                nerv.error("mismatching data dimension between %s and %s", from, to)
+            end
+            inputs[port_from] = {ref_to, port_to}
+            ref_to.inputs[port_to] = inputs -- just a place holder
+        elseif id_to == "<output>" then
+            _, output_dim = ref_from.layer:get_dim()
+            if output_dim[port_from] ~= dim_out[port_to] then
+                nerv.error("mismatching data dimension between %s and %s", from, to)
+            end
+            outputs[port_to] = {ref_from, port_from}
+            ref_from.outputs[port_from] = outputs -- just a place holder
+        else
+            _, output_dim = ref_from.layer:get_dim()
+            input_dim, _ = ref_to.layer:get_dim()
+            if output_dim[port_from] ~= input_dim[port_to] then
+                nerv.error("mismatching data dimension between %s and %s", from, to)
+            end
+            local mid = global_conf.mat_type(global_conf.batch_size,
+                                                output_dim[port_from])
+            local err_mid = mid:create() 
+
+            ref_from.outputs[port_from] = mid
+            ref_to.inputs[port_to] = mid
+
+            ref_from.err_inputs[port_from] = err_mid
+            ref_to.err_outputs[port_to] = err_mid
+
+            table.insert(ref_from.next_layers, ref_to) -- add edge
+            ref_to.in_deg = ref_to.in_deg + 1          -- increase the in-degree of the target layer
+        end
+    end
+    self.layers = layers
+    self.inputs = inputs
+    self.outputs = outputs
+    self.dim_in = dim_in
+    self.dim_out = dim_out
+end
+
+function nerv.DAGLayer:init(id) -- topology sort
+    local queue = {}
+    local l = 1
+    local r = 1
+    for id, ref in pairs(self.layers) do
+        if ref.in_deg == 0 then
+            table.insert(queue, ref)
+            nerv.utils.printf("adding source layer: %s\n", id)
+            r = r + 1
+        end
+    end
+    if l == r then
+        nerv.error("loop detected")
+    end
+    while l < r do
+        local cur = queue[l]
+        cur.visited = true
+        l = l + 1
+        for _, nl in pairs(cur.next_layers) do
+            nl.in_deg = nl.in_deg - 1 
+            if nl.in_deg == 0 then
+                table.insert(queue, nl)
+                r = r + 1
+            end
+        end
+    end
+    for i = 1, #queue do
+        nerv.utils.printf("queued layer: %s\n", queue[i].layer.id)
+    end
+    self.queue = queue
+    for id, ref in pairs(self.layers) do
+        -- check wether the graph is connected
+        if ref.visited == false then
+            nerv.utils.printf("warning: layer %s is ignored\n", id)
+        end
+        for i = 1, ref.input_len do
+            if ref.inputs[i] == nil then
+                nerv.error("dangling port %d of layer %s", i, id)
+            end
+        end
+        for i = 1, ref.output_len do
+            if ref.outputs[i] == nil then
+                nerv.error("dangling port %d of layer %s", i, id)
+            end
+        end
+        -- initialize sub layers
+        ref.layer:init()
+    end
+    for i = 1, #self.dim_in do
+        if self.inputs[i] == nil then
+            nerv.error("dangling port %d of layer <input>", i)
+        end
+    end
+    for i = 1, #self.dim_out do
+        if self.outputs[i] == nil then
+            nerv.error("dangling port %d of layer <output>", i)
+        end
+    end
+end
+
+function nerv.DAGLayer:set_inputs(input)
+    for i = 1, #self.dim_in do
+        local layer = self.inputs[i][1]
+        local port = self.inputs[i][2]
+        layer.inputs[port] = input[i]
+    end
+end
+
+function nerv.DAGLayer:set_outputs(output)
+    for i = 1, #self.dim_out do
+        local layer = self.outputs[i][1]
+        local port = self.outputs[i][2]
+        layer.outputs[port] = output[i]
+    end
+end
+
+function nerv.DAGLayer:set_err_inputs(bp_err)
+    for i = 1, #self.dim_out do
+        local layer = self.outputs[i][1]
+        local port = self.outputs[i][2]
+        layer.err_inputs[port] = bp_err[i]
+    end
+end
+
+function nerv.DAGLayer:set_err_outputs(next_bp_err)
+    for i = 1, #self.dim_in do
+        local layer = self.inputs[i][1]
+        local port = self.inputs[i][2]
+        layer.err_outputs[port] = next_bp_err[i]
+    end
+end
+
+function nerv.DAGLayer:update(bp_err, input, output)
+    self:set_err_inputs(bp_err)
+    self:set_inputs(input)
+    self:set_outputs(output)
+    for id, ref in pairs(self.queue) do
+        ref.layer:update(ref.err_inputs, ref.inputs, ref.outputs)
+    end
+end
+
+function nerv.DAGLayer:propagate(input, output)
+    self:set_inputs(input)
+    self:set_outputs(output)
+    for i = 1, #self.queue do
+        local ref = self.queue[i]
+        --[[
+        print(ref.inputs[1])
+        print(ref.outputs[1])
+        print(#ref.inputs, #ref.outputs)
+        --]]
+        ref.layer:propagate(ref.inputs, ref.outputs)
+    end
+end
+
+function nerv.DAGLayer:back_propagate(next_bp_err, bp_err, input, output)
+    self:set_err_outputs(next_bp_err)
+    self:set_err_inputs(bp_err)
+    self:set_inputs(input)
+    self:set_outputs(output)
+    for i = #self.queue, 1, -1 do
+        local ref = self.queue[i]
+        -- print(ref.layer.id)
+        ref.layer:back_propagate(ref.err_outputs, ref.err_inputs, ref.inputs, ref.outputs)
+         -- if #ref.err_outputs > 0 then
+         --     print(ref.err_outputs[1])
+         -- end
+    end
+end