How do I take the power of elements in a table?

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T4H14 2018-4-20

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https://ww2.mathworks.cn/matlabcentral/answers/396352-how-do-i-take-the-power-of-elements-in-a-table

编辑： Peter Perkins 2018-4-20

I have a table called NYLD1 and I want to create some new variables that are the squares and cubes of the variables columns 29:32 so I wrote the following:

cur_varnames = NYLD1.Properties.VariableNames;
for K = [29:32]
  thisvarname = cur_varnames{K};
  thisval = NYLD1.(thisvarname);
  sq_varname = [thisvarname '2'];
  cu_varname = [thisvarname '3'];
  NYLD1.(sq_varname) = thisval .^ 2;
  NYLD1.(cu_varname) = thisval .^ 3;
end

However, I get the following error when I run this:

Undefined function 'power' for input arguments of type 'table'.

How can I fix this?

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Peter Perkins 2018-4-20

编辑：Peter Perkins 2018-4-20

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It's funny. Some people seem to gravitate to using dot subscripting, some to braces. They both do "contents of", but I always suggest dot for one at a time, braces for multiple at a time. Nothing to do with your real question, but in this case I'd suggest

names = NYLD1.Properties.VariableNames(29:32);
sq_names = ...
cu_names = ...
NYLD1{:,sq_names} = NYLD1{:,names}.^2;
NYLD1{:,cu_names} = NYLD1{:,names}.^3;

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Answer 1

Peter Perkins 2018-4-20

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Based on the error you cite, it seems that one or more of those variables are themselves tables. Nothing wrong with that, you'll just have to do something slightly different.