[Tutor] sorting a 'large' datafile
Wilhelmsen Jan
Jan.Wilhelmsen@bilia.no
Tue Jul 22 10:02:22 2003
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I need to sort records in a datafile by specific positions in the file.
The records in the datafile look like this:
3000010711004943 200211052002110520021120015980050378
3000010711004943 200211052002110520021120015980050378
3200010711004943 200211052002110520021120015980050378
3100010711004943 200211052002110520021120015980050378
3000010711004943 200211052002110520021120015980050378
3000014211015894 200211052002110520021205030700161
3200014211015894 000000000451606+24 BD30599
3200014211015894 000000000158000+24 BD30599
3200014211015894 000000000033600+24 BD30599
3200014211015894 000000000025900+24 BD30599
3100014211015894 000000000038400+24 BD30599
I've created two variables for the fields I want to sort by:
rt = line[:2]
dok = line[6:16]
First I want to sort by 'dok' then by 'rt'.
Do I have to read the whole file into memory before I can begin sorting the
records?
I tried to read in all the lines but everything crashes when I do.
The file is only 250kb so this should be possibly, or I'm I wrong?
Can anyone give me some tips?
Thanks in advance
Jan Wilhelmsen
IT-Technician
Bilia Personbil as
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<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB style=
=3D'font-size:
10.0pt;font-family:Arial;mso-ansi-language:EN-GB'>I need to sort records in=
a <span
class=3DSpellE>datafile</span> by specific positions in the file.<o:p></o:p=
></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB style=
=3D'font-size:
10.0pt;font-family:Arial;mso-ansi-language:EN-GB'><o:p> </o:p></span><=
/font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB style=
=3D'font-size:
10.0pt;font-family:Arial;mso-ansi-language:EN-GB'>The records in the <span
class=3DSpellE>datafile</span> look like this:<o:p></o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB style=
=3D'font-size:
10.0pt;font-family:Arial;mso-ansi-language:EN-GB'><o:p> </o:p></span><=
/font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB style=
=3D'font-size:
10.0pt;font-family:Arial;mso-ansi-language:EN-GB'>3000010711004943<span
style=3D'mso-spacerun:yes'>
</span>200211052002110520021120015980050378<o:p></o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB style=
=3D'font-size:
10.0pt;font-family:Arial;mso-ansi-language:EN-GB'>3000010711004943<span
style=3D'mso-spacerun:yes'>
</span>200211052002110520021120015980050378<o:p></o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB style=
=3D'font-size:
10.0pt;font-family:Arial;mso-ansi-language:EN-GB'>3200010711004943<span
style=3D'mso-spacerun:yes'>
</span>200211052002110520021120015980050378<o:p></o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB style=
=3D'font-size:
10.0pt;font-family:Arial;mso-ansi-language:EN-GB'>3100010711004943<span
style=3D'mso-spacerun:yes'>
</span>200211052002110520021120015980050378<o:p></o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB style=
=3D'font-size:
10.0pt;font-family:Arial;mso-ansi-language:EN-GB'>3000010711004943<span
style=3D'mso-spacerun:yes'>
</span>200211052002110520021120015980050378<o:p></o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB style=
=3D'font-size:
10.0pt;font-family:Arial;mso-ansi-language:EN-GB'>3000014211015894<span
style=3D'mso-spacerun:yes'>
</span>200211052002110520021205030700161<span
style=3D'mso-spacerun:yes'> </span><o:p></o:p></span></fo=
nt></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB style=
=3D'font-size:
10.0pt;font-family:Arial;mso-ansi-language:EN-GB'>3200014211015894<span
style=3D'mso-spacerun:yes'>
</span>000000000451606+24<span
style=3D'mso-spacerun:yes'> =
</span>BD30599<span
style=3D'mso-spacerun:yes'> =
</span><o:p></o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB style=
=3D'font-size:
10.0pt;font-family:Arial;mso-ansi-language:EN-GB'>3200014211015894<span
style=3D'mso-spacerun:yes'>
</span>000000000158000+24<span
style=3D'mso-spacerun:yes'> =
</span>BD30599<span
style=3D'mso-spacerun:yes'> =
</span><o:p></o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB style=
=3D'font-size:
10.0pt;font-family:Arial;mso-ansi-language:EN-GB'>3200014211015894<span
style=3D'mso-spacerun:yes'>
</span>000000000033600+24<span
style=3D'mso-spacerun:yes'> =
</span>BD30599<span
style=3D'mso-spacerun:yes'> =
</span><o:p></o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB style=
=3D'font-size:
10.0pt;font-family:Arial;mso-ansi-language:EN-GB'>3200014211015894<span
style=3D'mso-spacerun:yes'>
</span>000000000025900+24<span
style=3D'mso-spacerun:yes'> =
</span>BD30599<span
style=3D'mso-spacerun:yes'> =
</span><o:p></o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB style=
=3D'font-size:
10.0pt;font-family:Arial;mso-ansi-language:EN-GB'>3100014211015894<span
style=3D'mso-spacerun:yes'>
</span>000000000038400+24<span
style=3D'mso-spacerun:yes'> =
</span>BD30599<span style=3D'mso-spacerun:yes'> &nbs=
p; &=
nbsp;
</span><o:p></o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB style=
=3D'font-size:
10.0pt;font-family:Arial;mso-ansi-language:EN-GB'><span
style=3D'mso-spacerun:yes'> </span><o:p></o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB style=
=3D'font-size:
10.0pt;font-family:Arial;mso-ansi-language:EN-GB'>I've created two variables
for the fields I want to sort by:<o:p></o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB style=
=3D'font-size:
10.0pt;font-family:Arial;mso-ansi-language:EN-GB'><o:p> </o:p></span><=
/font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB style=
=3D'font-size:
10.0pt;font-family:Arial;mso-ansi-language:EN-GB'><span
style=3D'mso-spacerun:yes'> </spa=
n><span
class=3DSpellE><span class=3DGramE>rt</span></span> =3D line[:2]<o:p></o:p>=
</span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB style=
=3D'font-size:
10.0pt;font-family:Arial;mso-ansi-language:EN-GB'><span
style=3D'mso-spacerun:yes'> </spa=
n><span
class=3DSpellE><span class=3DGramE>dok</span></span> =3D line[</span></font=
><st1:time
Hour=3D"6" Minute=3D"16"><font size=3D2 face=3DArial><span lang=3DEN-GB sty=
le=3D'font-size:
10.0pt;font-family:Arial;mso-ansi-language:EN-GB'>6:16</span></font></st1:=
time><font
size=3D2 face=3DArial><span lang=3DEN-GB style=3D'font-size:10.0pt;font-fam=
ily:Arial;
mso-ansi-language:EN-GB'>]<o:p></o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB style=
=3D'font-size:
10.0pt;font-family:Arial;mso-ansi-language:EN-GB'><o:p> </o:p></span><=
/font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB style=
=3D'font-size:
10.0pt;font-family:Arial;mso-ansi-language:EN-GB'>First I want to sort by '=
<span
class=3DSpellE>dok</span>' then by '<span class=3DSpellE>rt</span>'.<o:p></=
o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB style=
=3D'font-size:
10.0pt;font-family:Arial;mso-ansi-language:EN-GB'><o:p> </o:p></span><=
/font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB style=
=3D'font-size:
10.0pt;font-family:Arial;mso-ansi-language:EN-GB'>Do I have to read the who=
le
file into memory before I can begin sorting the records?<o:p></o:p></span><=
/font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB style=
=3D'font-size:
10.0pt;font-family:Arial;mso-ansi-language:EN-GB'><o:p> </o:p></span><=
/font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB style=
=3D'font-size:
10.0pt;font-family:Arial;mso-ansi-language:EN-GB'>I tried to read in all th=
e lines
but everything crashes when I do.<o:p></o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB style=
=3D'font-size:
10.0pt;font-family:Arial;mso-ansi-language:EN-GB'><o:p> </o:p></span><=
/font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB style=
=3D'font-size:
10.0pt;font-family:Arial;mso-ansi-language:EN-GB'>The file is only 250kb so=
this
should be possibly, or I'm I wrong?<o:p></o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB style=
=3D'font-size:
10.0pt;font-family:Arial;mso-ansi-language:EN-GB'><o:p> </o:p></span><=
/font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB style=
=3D'font-size:
10.0pt;font-family:Arial;mso-ansi-language:EN-GB'>Can anyone give me some t=
ips?<o:p></o:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB style=
=3D'font-size:
10.0pt;font-family:Arial;mso-ansi-language:EN-GB'><o:p> </o:p></span><=
/font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB style=
=3D'font-size:
10.0pt;font-family:Arial;mso-ansi-language:EN-GB'>Thanks in advance<o:p></o=
:p></span></font></p>
<p class=3DMsoNormal><font size=3D2 face=3DArial><span lang=3DEN-GB style=
=3D'font-size:
10.0pt;font-family:Arial;mso-ansi-language:EN-GB'><o:p> </o:p></span><=
/font></p>
<p class=3DMsoAutoSig><font size=3D3 face=3D"Times New Roman"><span lang=3D=
EN-GB
style=3D'font-size:12.0pt;mso-ansi-language:EN-GB;mso-no-proof:yes'>Jan
Wilhelmsen<o:p></o:p></span></font></p>
<p class=3DMsoAutoSig><font size=3D2 face=3D"Times New Roman"><span lang=3D=
EN-GB
style=3D'font-size:10.0pt;mso-ansi-language:EN-GB;mso-no-proof:yes'>IT-Tech=
nician<o:p></o:p></span></font></p>
<p class=3DMsoAutoSig><font size=3D2 face=3D"Times New Roman"><span lang=3D=
EN-GB
style=3D'font-size:10.0pt;mso-ansi-language:EN-GB;mso-no-proof:yes'>Bilia
Personbil as<o:p></o:p></span></font></p>
<p class=3DMsoNormal><font size=3D3 face=3D"Times New Roman"><span lang=3DE=
N-GB
style=3D'font-size:12.0pt;mso-ansi-language:EN-GB'><o:p> </o:p></span>=
</font></p>
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