Add nn.Sequential.remove([index])

Sequential.lua

@@ -15,14 +15,24 @@ end
 
 function Sequential:insert(module, index)
    index = index or (#self.modules + 1)
-   if index > (#self.modules + 1) then
+   if index > (#self.modules + 1) or index < 1 then
       error"index should be contiguous to existing modules"
    end
    table.insert(self.modules, index, module)
    self.output = self.modules[#self.modules].output
    self.gradInput = self.modules[1].gradInput
 end
 
+function Sequential:remove(index)
+   index = index or #self.modules
+   if index > #self.modules or index < 1 then
+      error"index out of range"
+   end
+   table.remove(self.modules, index)
+   self.output = self.modules[#self.modules].output
+   self.gradInput = self.modules[1].gradInput
+end
+
 function Sequential:updateOutput(input)
    local currentOutput = input
    for i=1,#self.modules do

doc/containers.md

@@ -51,7 +51,27 @@ which gives the output:
 [torch.Tensor of dimension 1]
 ```
 
-<a name="nn.Sequential.insert"/>
+<a name="nn.Sequential.remove"/>
+### remove([index]) ###
+
+Remove the module at the given `index`. If `index` is not specified, remove the last layer.
+
+```lua
+model = nn.Sequential()
+model:add(nn.Linear(10, 20))
+model:add(nn.Linear(20, 20))
+model:add(nn.Linear(20, 30))
+model:remove(2)
+> model
+nn.Sequential {
+  [input -> (1) -> (2) -> output]
+  (1): nn.Linear(10 -> 20)
+  (2): nn.Linear(20 -> 30)
+}
+```
+
+
+<a name="nn.Sequential.remove"/>
 ### insert(module, [index]) ###
 
 Inserts the given `module` at the given `index`. If `index` is not specified, the incremented length of the sequence is used and so this is equivalent to use `add(module)`.
@@ -70,6 +90,8 @@ nn.Sequential {
 }
 ```
 
+
+
 <a name="nn.Parallel"/>
 ## Parallel ##