Version (1.87 KB) by Jeremy
Splits a 1 x N array into N separate 1 x 1 variables. Improves SAVE time drastically.
Updated 19 Apr 2011

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Saving large (>2 GB) variables using the '-v7.3' flag is terribly slow, especially if the variable is not a simple matrix. If the large variable that is holding you up is a 1-D array, you can use SPLITVAR to break it up into separate variables in the workspace. This could allow you to save the workspace without the dreaded '-v7.3' flag. After reloading the workspace, use SPLICEVAR to build it back into the original variable.

I have a ~7.5GB 1x22 array of structures.

>> whos
Name Size Bytes Class
data 1x22 7580671154 struct

after running SPLITVAR(data) my workspace contains:

>> whos
Name Size Bytes Class
data_1 1x1 558955428 struct
data_10 1x1 182980944 struct
data_11 1x1 204706714 struct
data_12 1x1 240433764 struct
data_13 1x1 242623570 struct
data_14 1x1 257212788 struct
data_15 1x1 295351300 struct
data_16 1x1 277538660 struct
data_17 1x1 256249924 struct
data_18 1x1 218259258 struct
data_19 1x1 255908802 struct
data_2 1x1 469168036 struct
data_20 1x1 475334632 struct
data_21 1x1 469577114 struct
data_22 1x1 488044446 struct
data_3 1x1 499091734 struct
data_4 1x1 455919532 struct
data_5 1x1 481254514 struct
data_6 1x1 427976576 struct
data_7 1x1 445993342 struct
data_8 1x1 190239504 struct
data_9 1x1 187854604 struct

To return to the original variable, run:

Saving the original workspace with the '-v7.3' flag for me took a couple of hours. Using SPLITVAR takes less than a second, and using SAVE with no '-v7.3' flag takes a few minutes. Loading the workspace takes about a minute, and running SPLICEVAR to get the original variable back takes less than a second.

It wouldn't take much to modify to allow it to work with more than 1-D arrays!

Cite As

Jeremy (2024). splitvar/splicevar (https://www.mathworks.com/matlabcentral/fileexchange/31058-splitvar-splicevar), MATLAB Central File Exchange. Retrieved .

MATLAB Release Compatibility
Created with R2009b
Compatible with any release
Platform Compatibility
Windows macOS Linux
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