CAddTable.lua

local CAddTable, parent = torch.class('nn.CAddTable', 'nn.Module')

function CAddTable:__init(ip)
 parent.__init(self)
 self.inplace = ip
 self.gradInput = {}
end

function CAddTable:updateOutput(input)
 if self.inplace then
 self.output:set(input[1])
 else
 self.output:resizeAs(input[1]):copy(input[1])
 end
 for i=2,#input do
 self.output:add(input[i])
 end
 return self.output
end

function CAddTable:updateGradInput(input, gradOutput)
 for i=1,#input do
 self.gradInput[i] = self.gradInput[i] or input[1].new()
 if self.inplace then
 self.gradInput[i]:set(gradOutput)
 else
 self.gradInput[i]:resizeAs(input[i]):copy(gradOutput)
 end
 end

 for i=#input+1, #self.gradInput do
 self.gradInput[i] = nil
 end

 return self.gradInput
end