Incrementally growing and adding to a matrix
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Hello,
I'm new to matlab and am having a lot of trouble figuring out how to add elements to a matrix while simultaneously increasing the value of the existing elements.
For example, if my increment of change is .2, then i would want each number in my matrix to grow by .2 during each timestep. However, I also need to be making the matrix one element larger at each timestep.
t1 = .2 t2 = .4 .2 t3 = .6 .4 .2
I'm kind of at a loss, so any help would be greatly appreciated!
etc, etc.
回答（3 个）
Jan
2011-4-1
t = [];
for i=1:100
t = [t, 0] + 0.2; % Or [t + 0.2, 0.2];
end
Another method:
for i = 1:100;
t = (i:-1:1) * 0.2;
end
Be aware that a growing array is a very inefficient method. It is better to create the vector once and use indexing to operate on parts:
tFull = (100:-1:1) * 0.2;
for i = 1:100
t = tFull(101-i:100);
end
Sean de Wolski
2011-4-1
Don't do this!!
t = 0.2:0.2:maxt
or; if you need what you have above
t = tril(toeplitz(0:.2:1));
t(3,:)
1 个评论
Jan
2011-4-2
The FAQ concerns the formulation "t1=..., t2=...". As fas as I understand, the OP does not really want to create these different variables explicitely. If he does: Please follow Sean's link. +1
Aryn
2011-4-1
0 个投票
1 个评论
Sean de Wolski
2011-4-1
If you give us an idea of the bigger picture we can probably help you refine the global approach as well as just creating t.
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