I use writeseq. Yesterday I ran a process that selects a number of
files, parses them into special formats, and writes them out.

I created 65 files, 106 MB. Total time: 4 minutes. 

UD 5.1.27, Windows 2003

However, if you are writing to a "dir" file then you can use either a
dynamic array or dimensioned (make sure you put something in each "row"
or you will get an unassigned variable error) and simply write to the
file. I find the writeseq faster.

I use the "best of both worlds" and do:
OPENSEQ 'dir type file', 'txt file' TO myfile ELSE STOP
WRITESEQ line APPEND ON myfile ELSE STOP

This way I don't have a hard-coded file path in my code and can simply
move the file around by changing the VOC pointer.

Hth
Colin Alfke
Calgary, Canada

>-----Original Message-----
>From: Jeffrey Butera
>
>I'm going to ask yet another dumb question - Unidata 6.1.4 on 
>Solaris (soon to be 7.1.x).
>
>I'm selecting a bunch of records and then outputting data from 
>them into an ascii file in _HOLD_.  If I open a sequential 
>file, write the data 
>line-by-line (WRITESEQF) and close the file, it takes about 5 
>minutes.   If I 
>save the data in a @FM delimited record and then write the 
>record out at the end, it takes about 3 seconds.
>
>I'm well aware that writing sequentially is doing a whole lot 
>more disk I/O but I can't believe the difference in speed.  
>Are their any subtleties other than disk I/O?  I seem to 
>recall some discussion about seq files and maintaining the 
>pointer of where the current position in the file, but I'm 
>foggy on these topics...
>
>-- 
>Jeff Butera, Ph.D.
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