From: Robert Klemme <bob.news@...>
Date: 2004-05-24T17:38:44+09:00
Subject: Re: Fortran Format?


"Mark Sparshatt" <msparshatt@yahoo.co.uk> schrieb im Newsbeitrag
news:40ABD8AF.6020500@yahoo.co.uk...
> Qubert wrote:
>
> >OK, I have an algorithm that I created to format a series of numbers
> >for a column centric FORTRAN routine to use.  I don't like what I have
> >created, although it works, so I would like to ask if anyone here has
> >a more cleaver way.
> >
> >Problem:  I have a series of numbers that need to be formated as a
> >FORTRAN program would.  That is, FORTRAN cares more about columns than
> >numbers so I need to fake the output of Ruby to make it look "decimal
> >justified".
> >
> >Example, a series of numbers:
> >3.15, 122.5, 303.123, 55.0
> >Input for C or Ruby (the space means a new number):
> >3.15 122.5
> >303.123 55.0
> >Input needed for FORTRAN with format (f7.3,f5.1):
> >  3.150122.5
> >303.123 55.0
> >
> >My Ruby hack to put spaces at the begining if necessary:
> >def ff(num,len1,len2)
> >  x = num.to_s.split(".")
> >  numstring = ""
> >  x[0].size.upto(len1 - 1) {|b| numstring << ' '}
> >  numstring << x[0] << "."
> >  numstring << x[1][0..len2]
> >end
> >
> >code...
> >bla ...
> >printf("%s %s\n", ff(3.150,3,3),ff(122.5,3,1)
> >printf("%s %s\n", ff(303.123,3,3),ff(55.0,3,1)
> >
> >
> >
> A better way would be to be to use the sprintf method (documented on
> page 427 of the pickaxe) to format the string.
>
> The following code does what you want
>
> def ff(num, len1, len2)
>     sprintf("%#{len1 + len2 + 1}.#{len2}f", num)
> end

sprintf can already handle widths as arguments:

sprintf( "%*.*f", len1 + len2, len2, num )

> printf("%s %s\n", ff(3.150,3,3),ff(122.5,3,1))
> printf("%s %s\n", ff(303.123,3,3),ff(55.0,3,1))

>> printf "%*.*f %*.*f\n", 7, 3, 3.150, 5, 1, 122.5
  3.150 122.5

:-)

    robert

>
>
> >I know that this needs improvement so your help would be appreciated.
> >I have to interface with these types of FORTRAN programs a lot, thus
> >far I have avoided this.
> >
> >
> HTH
>
> --
>
> Mark Sparshatt
>
>