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Pascal A. Dupuis-4

I've an application where I have to generate a csv file in order to
save a lot of things.

To generate it, I use code similar to:

fields={'Frequency', '%d';
        'Span', '%f'};
where the first column is the field name and the second the
format. Then I concatenate the second colum in something like  
format = "%d, %f\n"

After the computation, I generate a line as:
  fprintf(OUT, format, var1, var2, ...)

The problem is to change the coding, with the time I had to add some
more variables, ...

A possible way to cope with this would be to allow a cell to contain code:
fields={'Frequency', '%d', 'freq';
        'Span', '%f', 'span';
        'Std Err', '%f', 'sqrt(sig2(1,1))' };
This way generating an output line would simply require evaluating the third
column elements.

So, a question about performances: as the content in the third column
is constant, are things like:

for indk = 1.. 100,
  %# do some computation
  for indi=1:rows(fields)
    fprintf(OUT, fields(indi,2), eval(fields(indi, 3)));

optimised, i.e. compiled only once, or should I construct something like:

for indi=1:rows(fields)
    cmd = [ cmd "," fields(indi, 3) ];
cmd = [cmd "]"];

for indk = 1.. 100,
  %# do some computation
  fprintf(OUT, format, eval(cmd))

Or is it simply possible to somehow arrange a cell element
to contain code  which would be compiled only once ?



Dr. ir. Pascal Dupuis
K. U. Leuven, ESAT/ELECTA (formerly ELEN):  http://www.esat.kuleuven.ac.be/
Kasteelpark Arenberg, 10; B-3001 Leuven-Heverlee, Belgium
Tel. +32-16-32 10 21 -- Fax +32-16-32 19 85