First install Torch7 (www.torch.ch) then simply install this package using luarocks:
luarocks install csvigo
The library provides 2 high-level functions: csvigo.load and csvigo.save. To get help on these functions, simply do:
> csvigo.save()
> csvigo.load()
Loading a CSV file in 'query' mode gives you a convenient query function that you can use to query subsets of your original CSV file. To get help on this query function, simply do:
> query = csvigo.load{path='somefile.csv', mode='query'}
> query('help')
-- print some help
> all = query('all')
> subset = query('union', {somevar=someval, someothervar={val1, val2}})
CSVigo supports efficient loading of very large CSV files into memory. The loaded data structure is a read-only table with efficiency hidden under the hood.
Loading:
m = csvigo.load({path = "my_large.csv", mode = "large"})
Printing by default only prints first 10 and last 10 rows
print(m)
Individual element access
print(m[32])
Size of table:
print(#m)
For loop over entries:
Type 1:
for i=1, #m do
print(m[i]) -- get element
end
Type 2:
for k,v in ipairs(m) do
print(k)
print(v)
end
Type 3:
for k,v in pairs(m) do
print(k)
print(v)
end
Read-only table
-- read only table, will error here:
m[13] = 'a'