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Can I change datatype in j

I loaded my data in a table in j. Since they are all prices and I need to calculate returns, I realize that the datatypes of all cells are literal. How can I change it to floating type? Thanks!

Solution

  • As long as the literals are all numerals you can use dyadic ".(Numbers)

    http://www.jsoftware.com/help/dictionary/d601.htm

    The left argument is a numeral that will replace any illegal characters.

       3 10 $ '23 223 1  3 5 334.05 1 4 3.6e3' NB. String
23 223 1  
3 5 334.05
 1 4 3.6e3
   0 ". 3 10 $ '23 223 1  3 5 334.05 1 4 3.6e3' NB. conversion to numeric
23 223      1
 3   5 334.05
 1   4   3600
   2 * 0 ". 3 10 $ '23 223 1  3 5 334.05 1 4 3.6e3' NB. Multiplying wouldn't work if it was a string!
46 446     2
 6  10 668.1
 2   8  7200

    There may be some work to be done to be sure that the literal table is all numeric symbols ( ". won't convert '$' or alphabet characters.

       0 ". '$23.01' NB. returns 0 since '$'is not numeric
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