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export - DumpSave for the forgetful


A few weeks ago I created a big matrix, and in order not to have to recreate it, I stored it using DumpSave["file.mx", variable]. Now I want to read it back in and so I use <. It appears to work fine and to load the file (which takes a few moments because it is 54 MB in size). Now the problem: I have forgotten what I called the matrix, that is, what name variable I used in when I saved it. My generating command is unfortunately not around any more. Is there any way of figuring out what my variable was called or more directly, how to access my data now that it is loaded?



Answer



I think you can use Names["Global`*"] to get the name:



a = RandomReal[{0, 1}, 10];
SetDirectory[$TemporaryDirectory];
DumpSave["1.mx", a];

Quit[]

SetDirectory[$TemporaryDirectory];
<< 1.mx
Names["Global`*"]


(*{"a"}*)

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