How to run this Lua code?

[chunyi0219]

Has anyone successfully run this code?
I'm a Lua novice, and I tried to run the code on Ubuntu 20.04.
Torch has been installed on my Linux.

[chunyi0219]

chunyi@chunyi-VirtualBox:~/DeepKnowledgeTracing/scripts$ th trainAssist.lua
/home/chunyi/torch/install/bin/luajit: trainAssist.lua:18: assertion failed!
stack traceback:
[C]: in function 'assert'
trainAssist.lua:18: in function 'run'
trainAssist.lua:132: in main chunk
[C]: in function 'dofile'
...unyi/torch/install/lib/luarocks/rocks/trepl/scm-1/bin/th:150: in main chunk
[C]: at 0x00405d50

chunyi@chunyi-VirtualBox:~/DeepKnowledgeTracing/scripts$ th trainAssist.lua testLoading khan...
/home/chunyi/torch/install/bin/luajit: ./dataAssist.lua:95: attempt to call global 'split' (a nil value)
stack traceback:
./dataAssist.lua:95: in function 'loadStudent'
./dataAssist.lua:30: in function '__init'
/home/chunyi/torch/install/share/lua/5.1/class/init.lua:164: in function 'DataAssistMatrix'
trainAssist.lua:22: in function 'run'
trainAssist.lua:132: in main chunk
[C]: in function 'dofile'
...unyi/torch/install/lib/luarocks/rocks/trepl/scm-1/bin/th:150: in main chunk
[C]: at 0x00405d50

[chunyi0219]

I run the commands as, then show up the errors as above.