Re: cell2csv (io package): Higher precision of floating point numbers?

[Martin Kunz]

Not that many people need so much precision. Any idea what number of digits
are output by e.g., csvwrite ?

Easy enough to test:

a=[1,1.1,1.111111,1.11111111111111111],csvwrite("ones.csv",a)

creates a file that contains:

1,1.1,1.111111,1.111111111111111

i.e. a maximum of 16 significant digits. eps() is 2.2E-16, so csvwrite uses the full precision of double values. In the light of csvwrite's behaviour I would suggest

sprintf(tmp, "%.16g", c(i, j).double_value());

for the new cell2csv.cc .

If users do not need this precision and would like to keep files small, they can always round floating numbers to the desired precision prior to writing them to a file.

Cheers,

Martin