Finding difference between two rows

Question

Karina 2018-4-25

1
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此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/397259-finding-difference-between-two-rows

评论： Dooyoung Kim 2018-6-28

I have a 6696502 x 2 table which shows energy in MW for a period of time. I want to add a column which is the difference in energy for each time period so column 3 row 2 shows the difference in values for row 2 and 1 in column 2.

I have the following code, however it is very slow to compute given my table is so large. if true

if true
  % code
for n = 1:countReg
          if n == 1
              diffReg = 0;
          else
              diffReg = RegCol(n) - RegCol(n-1);
          end
          newRegTable.ChangeReg(n) = diffReg;       
      end
end