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Convert symbol to a list of symbols

I read in a csv file:

csvFile:1!("SSS"; enlist ",") 0: hsym `$"\\\\location\\of\\csv";

But lists of symbols are read as single symbols. e.g. in the csv file I have 'a'b'c but 

csvFile`some_keyed_value
`col1`col2!``a`b`c`

What I want is this - and note how a single ticker should be an empty list:

`col1`col2!(`a`b`c;())

Is there a way to make this cast or read in the csv differently or modify the csv so that it reads in correctly? Any modifications I make to the csv (e.g. replacing ' with () ) simply converts it to a single symbol (e.g. I get '() ).

Here is a screenshot of a few lines from the csv

enter image description here

Solution

  • Taking this csv as an example:

    cat ex.csv
x,y
`aa`bb,
`cc`dd,`ee`ff
,`gg`hh

    You need to load those nested symbol columns in as strings first:

    q)show tab:("**";enlist",")0:`:ex.csv
x        y
-----------------
"`aa`bb" ""
"`cc`dd" "`ee`ff"
""       "`gg`hh"

    From here you then need to drop the backticks and convert the strings to symbols. One possible way to do this is:

    q)update {`$1_'where["`"=x]cut x}'[x] from tab
x          y
-------------------
`aa`bb     ""
`cc`dd     "`ee`ff"
`symbol$() "`gg`hh"