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I have a set of arrays I would like to output to some file ArrayStorage.txt s.t. these arrays could be read-in to a separate notebook on a separate kernel. Is there an easy way to export a set of arrays?

halirutan
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FaintingWater
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    "Is there an easy way to export a set of arrays" — the question seems to imply that existing methods are difficult. Have you tried looking in the help center? (press F1) – rm -rf Mar 14 '13 at 23:42
  • @rm-rf Exporting a single array looks pretty simple, but I'm asking about exporting and importing a list of arrays? – FaintingWater Mar 14 '13 at 23:44
  • @FaintingWater A list of arrays is just a tensor of a higher rank. The question is: For which application do you want to export it? – halirutan Mar 14 '13 at 23:48
  • @halirutan For Mathematica. I would like a single file where I can reload all of my variables from another notebook after quitting the kernel? – FaintingWater Mar 14 '13 at 23:57
  • can you be more specific? do you have a number of variables, say a, b and c, and would like to export them such that you can later re-import them all into the same variables? ie, run something and end up with the same array in each of a, b and c that you had earlier? or just one tensor of rank>2? – acl Mar 15 '13 at 00:01
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    Then DumpSave is worth a look. You find it e.g. here in this question http://mathematica.stackexchange.com/q/121/187 – halirutan Mar 15 '13 at 00:01

2 Answers2

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If you want to save definitions, then DumpSave is one way to go:

a = RandomReal[1, 1000];
b = RandomInteger[10, 10000];
c = {blub, boing, ups};

DumpSave["tmp/out.mx", {a, b, c}];

Now you can quit the kernel or restart Mathematica and with

<< "tmp/out.mx"

a, b and c have their old values again.

One thing you should note is that files written by DumpSave can only be read on the same type of computer system on which they were written.

halirutan
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0

Another way was suggested by David Bailey on MathGroup late last year (https://groups.google.com/forum/?fromgroups=#!searchin/comp.soft-sys.math.mathematica/david$20bailey%7Csort:date/comp.soft-sys.math.mathematica/lf-EJeiqDwY/eEF29xJUFZwJ).

Briefly, as an alternative to MX files, try

 str=OpenWrite[file,BinaryFormat->True]; 
       BinaryWrite[str,magic,"TerminatedString"]; 
       BinaryWrite[str,Compress[{expr,version}],"TerminatedString"]; 
       Close[str];

to save, and 

str=OpenRead[file,BinaryFormat->True]; 
    If[BinaryRead[str,"TerminatedString"]==magic, 
       expr=Uncompress[BinaryRead[str,"TerminatedString"]]; 
       ]; 
    Close[str];

to read.

dwa
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