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Structure fields to variables

version 1.1.0.1 (2.09 KB) by Matt J
Code writing tool for importing/exporting workspace variables to or from a struct.

3.6K Downloads

Updated 29 Jul 2019

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Structures are a convenient way of carrying around many variables as a single object and of passing those variables to a function packed in a single argument.
Once a structure has been passed to a function, however, many users (according to various Newsgroup posts) find it tiresome to have to access its fields repeatedly through dot-indexing notation and have sought automated ways to take a structure and assign all of its fields to separate variables, as in
a = myStruct.a;
b = myStruct.b;
c = myStruct.c;
etc...
Solutions based on assignin() have often been tried, but are hazardous, for reasons discussed, for example, in this thread:

http://www.mathworks.com/matlabcentral/newsreader/view_thread/244639#628695

The structvars() tool in this FEX submission does something virtually as good and far safer.

Given a structure, it will print the lines of code needed to assign structure fields to separate variables (or the reverse). The lines of code can be conveniently copy/pasted from the command window to the file editor at the location in the file where the variables need to be unpacked.


Examples: Given structure myStruct, with fields a,b,c, & d

(1) structvars(myStruct) %assign fields to variables

ans =

a = myStruct.a;
b = myStruct.b;
c = myStruct.c;
d = myStruct.d;

(2) structvars(3,myStruct) %split the last result across 3 columns

ans =

a = myStruct.a; c = myStruct.c; d = myStruct.d;
b = myStruct.b;

(3) structvars(3,myStruct,0) %assign variables to fields

ans =

myStruct.a = a; myStruct.c = c; myStruct.d = d;
myStruct.b = b;

The commands can obviously be regenerated if you add/remove structure fields later on. On the other hand, the effort of just making these incremental edits manually is typically minimal.

Cite As

Matt J (2021). Structure fields to variables (https://www.mathworks.com/matlabcentral/fileexchange/26216-structure-fields-to-variables), MATLAB Central File Exchange. Retrieved .

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

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