| Re: [Q] Reading from ASCII file? [message #12253] |
Fri, 24 July 1998 00:00 |
mgs
Messages: 144
Registered: March 1995
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Senior Member |
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In article <35B6E8E9.75FCB5A3@ramses.tss.no>, gunnarlr@phys.uit.no wrote:
> Hi!
>
> I'm reading UTM map coordinates from an ASCII file, which has lines
> like:
> 681765.37 7450650.54 334 1
>
> I read this with code on the form:
> while (NOT EOF(unit)) do begin
> format='(2D,2I)'
> readf,unit,temp1,temp2
> UTMcoords(*,i)=temp1
> pixelcoords(*,i)=temp2
> i=i+1
> endwhile
> (all relevant variables in double format)
>
> Everything works out fine, exept that the second column is rounded off:
> 7450650.54 ---> 7450650.5
> that is: 8 numbers in any case (before or after the decimal-point). "So
> what?" you're saying? The problem is that I really need all my 9
> numbers. Anyone got an idea??
>
> Regards,
> Gunnar L. Rasmussen, Applied Physics, Univ. of Tromsoe, Norway
I suspect your data is read and stored intact, but printed in a rounded
format. Look at the Print, Format=() commands to see what's actually in
the variables.
--
Mike Schienle Interactive Visuals
mgs@la.znet.com http://la.znet.com/~mgs/
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| Re: [Q] Reading from ASCII file? [message #12261 is a reply to message #12253] |
Thu, 23 July 1998 00:00  |
Vap User
Messages: 31
Registered: April 1998
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Member |
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TSS Operator on duty <operator@ramses.tss.no> writes:
I think the 'D' format assumes the numbers are 'float' as opposed to
'double' so there will probably be some rounding. In any case, perhaps
the following will work, and be faster than the loop.
Say there are 'Nlines' lines in the file.
tmp=dblarr(4,nlines)
readf, unit, tmp
UTMCoords = tmp(0:1,*)
pixelcoords = long( tmp(2:3,*) ) ; perhaps 'fix' instead of long?
tmp=0 ;be nice to your fellow users!
close, unit
This assumes there are always four columns.
whd
>
> Hi!
>
> I'm reading UTM map coordinates from an ASCII file, which has lines
> like:
> 681765.37 7450650.54 334 1
>
> I read this with code on the form:
> while (NOT EOF(unit)) do begin
> format='(2D,2I)'
> readf,unit,temp1,temp2
> UTMcoords(*,i)=temp1
> pixelcoords(*,i)=temp2
> i=i+1
> endwhile
> (all relevant variables in double format)
>
> Everything works out fine, exept that the second column is rounded off:
> 7450650.54 ---> 7450650.5
> that is: 8 numbers in any case (before or after the decimal-point). "So
> what?" you're saying? The problem is that I really need all my 9
> numbers. Anyone got an idea??
>
> Regards,
> Gunnar L. Rasmussen, Applied Physics, Univ. of Tromsoe, Norway
>
--
I don't speak for JPL, it doesn't speak for me.
Well, not all the time, at least.
William Daffer <vapuser@haifung.jpl.nasa.gov>
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