How to pass control from one loop to the other loop

2 views (last 30 days)
Sai on 14 Oct 2015
Edited: Stephen23 on 16 Oct 2015
My aim is to alter a data sample in such a way that the sign of values in between 0.01 to next 0.01 are altered.
Like for example; if given sample is
{0.3,0.21,0.9,0.3,0.01,0.3,0.4,0.32,0.01,0.9,0.97}
My code has to give the output as
{0.3,0.21,0.9,0.3,0.01,-0.3,-0.4,-0.32,0.01,0.9,0.97}
So, I'm trying to write a nested loop to read the sample and alter the sign in between 0.01 to next 0.01
for n=1:100000
if u(n)=0.01
for m=n+1:10000
if u(m)=0.01
% switch to the original 'n' loop
end
u(m)=-1*u(m);
end
end
end
But, I'm unable to switch to the original loop. Anyone suggest, how can I switch between them ?

Thorsten on 14 Oct 2015
Edited: Thorsten on 14 Oct 2015
invert = 1;
for i = 1:numel(u)
if u(i) == 0.01
invert = -invert;
elseif invert<0
u(i) = -u(i);
end
end
Sai on 15 Oct 2015

Eng. Fredius Magige on 14 Oct 2015
try this
for n=1:100000 if(find(sample(:)==0.01,1)=<find(sample(:)==0.01,2)) % sample is your data num=-1*sample(:,n) else num=sample(:,n) end
Sai on 15 Oct 2015
Thanks for your suggestion :). It worked

Stephen23 on 14 Oct 2015
Edited: Stephen23 on 14 Oct 2015
There is no need for slow and inefficient loops when code vectorization is faster and neater:
>> tol = 0.0005;
>> val = 0.01;
>> V = [0.3,0.21,0.9,0.3,0.01,0.3,0.4,0.32,0.01,0.9,0.97];
>> idx = abs(V-val)<tol;
>> idy = mod(cumsum(idx),2);
>> idz = (-1).^(idy&[false,idy(1:end-1)]);
>> V.*idz
ans =
0.3 0.21 0.9 0.3 0.01 -0.3 -0.4 -0.32 0.01 0.9 0.97
Stephen23 on 16 Oct 2015
Edited: Stephen23 on 16 Oct 2015
My pleasure. You can also vote for answers that introduce you to new concepts!

Categories

Find more on Loops and Conditional Statements in Help Center and File Exchange

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!