How do I create efficient instance variable mutators in Matlab?
- by Trent B
Previously, I implemented mutators as follows, however it ran spectacularly slowly on a recursive OO algorithm I'm working on, and I suspected it may have been because I was duplicating objects on every function call... is this correct?
%% Example Only
obj2 = tripleAllPoints(obj1)
obj.pts = obj.pts * 3;
obj2 = obj1
end
I then tried implementing mutators without using the output object... however, it appears that in MATLAB i can't do this - the changes won't "stick" because of a scope issue?
%% Example Only
tripleAllPoints(obj1)
obj1.pts = obj1.pts * 3;
end
For application purposes, an extremely simplified version of my code (which uses OO and recursion) is below.
classdef myslice
properties
pts % array of pts
nROW % number of rows
nDIM % number of dimensions
subs % sub-slices
end % end properties
methods
function calcSubs(obj)
obj.subs = cell(1,obj.nROW);
for i=1:obj.nROW
obj.subs{i} = myslice;
obj.subs{i}.pts = obj.pts(1:i,2:end);
end
end
function vol = calcVol(obj)
if obj.nROW == 1
obj.volume = prod(obj.pts);
else
obj.volume = 0;
calcSubs(obj);
for i=1:obj.nROW
obj.volume = obj.volume + calcVol(obj.subs{i});
end
end
end
end % end methods
end % end classdef
