Lua throws error luajit: error loading module 'libpaths' from file - lua

Question

I have lua 5.2, Torch version 7, Ubuntu version 14.04 trusty Installed
I am trying to run the following code
++++++++++++++++++++++code++++++++++++++++++++++++++++++++++++++++++++
require 'neuralconvo' require 'xlua'
-- Load Dataset
print("--Loading Dataset")
dataset=neuralconvo.Dataset(neuralconvo.CornellMovieDiaogs("data/cornell_movie_diaogs"),
{ loadFirst = options.dataset,
minWordFreq = options.minWordFreq
})
--Build Model
model = neuralconvo.Seq2Seq(dataset.wordsCount, options.hiddenSize) model.goToken = dataset.goToken
model.eosToken=dataset.eosToken
--Training Parameters
model.criterion=nn.SequencerCriterion(nn.ClassNLLCriterion())
model.learningRaw = options.learningRate
model.momentum = otions.momentum
local decayFactor = (options.minLR - options.learningRate)/options.saturateEpoch local minMeanError = nil
--Enable Cuda
if options.cuda then
require 'cutorch'
require 'cunn'
elseif options.opencl then
require 'cltorch'
require 'clnn'
model:cl()
end
-- Train Model using backpropogation
for epoch = 1,options.maxEpoch do
local errors = torch.Tensor(dataset.examplesCount):fill(0)
local timer=torch.timer()
local i=1
for examples in dataset:batches(options.batchSize) do
collectgarbage()
for _, example in ipairs(examples) do
local input, target = unpack(examples) do
if options.cuda then
input = input:cuda()
target = target:cuda()
elseif options.opencl then
input = input:cl()
target = target:cl()
end
local err=model:train(input, target)
if err ~= err then
error("Invalid error! Exiting.")
end
errors[i] = err
xlua.progress(i, dataset.examplesCount)
i=i+1
end
end
timer:stop()
--Save the model if not Improved
if minMeanError == nil or errors:mean() < minMeanError then
print("\n(Saving model...)")
torch.save("data/model.t7",model)
minMeanError=errors:mean()
end
-- Update Learning Rate
model.learningRate = model.learningRate + decayFactor
model.learningRate = math.max(options.minLR,model.learningRate)
end
end
=============================================================
I get the following error
luajit: error loading module 'libpaths' from file '/home/guru99u2/torch/install/lib/lua/5.2/libpaths.so':
/home/guru99u2/torch/install/lib/lua/5.2/libpaths.so: undefined symbol: luaL_setfuncs
stack traceback:
[C]: at 0x00450240
[C]: in function 'require'
/home/guru99u2/torch/install/share/lua/5.2/paths/init.lua:1: in main chunk
[C]: in function 'require'
/home/guru99u2/torch/install/share/lua/5.2/torch/init.lua:12: in main chunk
[C]: in function 'require'
./neuralconvo.lua:1: in main chunk
[C]: in function 'require'
bot.lua:1: in main chunk
[C]: at 0x00404d60

Answer 1

Something went wrong during the installation process (or you didn't clean the previous version) as you are trying to use modules built for Lua 5.2 with the interpreter that supports Lua 5.1 ABI (LuaJIT in this case). As the result you get that error undefined symbol: luaL_setfuncs because the dynamic library expects to have the function, but the loaded interpreter doesn't provide it.
Torch supports both LuaJIT and Lua 5.2, but you need to run ./clean.sh script as indicated in the documentation when switching Lua versions.