st: Reshape problem

[Johan Hellström <johan.hellstrom@pol.umu.se>]

Dear all,

I have a dataset that is in long form (containing a lot of variables), but some variables (v1-v34 in the example below) are measured at a different level and stored in wide form. That is, it is the same variable for different sub-units.  These also contain a lot of empty cells. Does anyone know a way to create a new panel where all "wide form"-variables (V1-V34) is coverted into long form (and the values stored in a 'New-variable'). The example below gives an indication of how my dataset looks like. For each 'Unit' it is about 10-25 measurement points over time (unbalanced panel). 

Old panel:
----------------------------------------------------------------------------------------------------------------------------------------------------
Unit	Time	x1	V1	V2	V3	V4	...	v34
1	1	12.3	.	67	26	48	...	23
1	2	26.6	45	34	12	.	...	64

...

2	1	84.0	83	.	.	23	...	87
2	2	23.5	.	.	91	82	...	98

...
----------------------------------------------------------------------------------------------------------------------------------------------------


New panel:
-----------------------------------------------------------------------------------------------------
Unit	Sub-unit	Time	x1	New-variable
1	1	1	12.3	.
1	2	1	12.3	67
1	3	1	12.3	26
1	4	1	12.3	48
...
1	34	1	12.3	23
1	1	2	26.6	45
1	2	2	26.6	34
1	3	2	26.6	12
1	4	2	26.6	.
...

2	1	1	84.0	83
2	2	1	84.0	.
2	3	1	84.0	.
2	4	1	84.0	23
...
2	34	1	84.0	87
2	1	2	23.5	83

Etc.
------------------------------------------------------------------------------------------------------	

Thanks,
Johan Hellstrom



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