# st: RE: RE: reshaping a data file: cell frequency = number of rows in the new data set

 From "Scott Merryman" <[email protected]> To <[email protected]> Subject st: RE: RE: reshaping a data file: cell frequency = number of rows in the new data set Date Fri, 17 Dec 2004 05:01:43 -0600

```> -----Original Message-----
> From: [email protected] [mailto:owner-
> [email protected]] On Behalf Of G. ter Riet
> Sent: Friday, December 17, 2004 2:20 AM
> To: [email protected]
> Subject: st: RE: reshaping a data file: cell frequency = number of rows in
> the new data set
>
> Hi Scott,
> now the data are structured as (data editor view)
> a b c d
> 1 2 3 4
> where a thru' d are the variable names denoting the cell frequencies;
> a=true positive test results; b=false positives; c=false negatives;
> d=true negatives.
>
> Gerben ter Riet, MD PhD, Amsterdam
>

Here is one way to accomplish this:

. l , noobs

+-------------------+
| tp   fp   fn   tn |
|-------------------|
|  1    2    3    4 |
+-------------------+

. xpose, clear varname

. expand v1
(6 observations created)

. sort v

. rename _v gold

. mark v2 if gold =="tp" | gold == "fn"

. l , noobs

+----------------+
| v1   gold   v2 |
|----------------|
|  1     tp    1 |
|  2     fp    0 |
|  2     fp    0 |
|  3     fn    1 |
|  3     fn    1 |
|----------------|
|  3     fn    1 |
|  4     tn    0 |
|  4     tn    0 |
|  4     tn    0 |
|  4     tn    0 |
+----------------+

Keep in mind that -xpose, clear- will drop any string variables.

Hope this helps,
Scott

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```

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