How to use 'trapz' command to calculate the area under the curve for each time gap of a graph?

          T          Y
          1.00       2988.00
          1.00       2966.00
          1.00       2915.00
          1.00       2891.00
          1.00       2833.00
          1.02       2846.00
          1.19       2829.00
          1.39       2799.00
          1.66       2806.00
          1.80       2804.00
          2.00       2834.00
          2.19       2827.00
          2.39       2897.00
          2.66       2889.00
          2.80       2864.00
          3.02       2874.00
          3.19       2890.00
          3.39       2874.00
          3.64       2964.00
          3.80       3059.00
          4.02       3109.00
          4.19       3214.00
          4.39       3292.00
          4.66       3334.00
          4.80       3443.00
          5.00       3515.00
          5.19       3614.00
          5.39       3736.00
          5.66       3789.00
          5.80       3811.00
          6.00       3892.00
          6.20       3954.00
          6.41       3985.00
          6.66       4039.00
          6.80       4039.00
          7.00       4045.00
          7.19       4040.00
          7.39       3977.00
          7.66       3918.00
          7.80       3961.00
          8.02       3955.00
          8.19       3923.00
          8.39       3988.00
          8.66       4064.00
          8.80       4001.00
          9.00       3991.00
          9.19       4043.00
          9.39       4021.00
          9.66       3970.00
          9.80       3967.00
         10.00       3932.00
         10.19       3856.00
         10.39       3794.00
         10.66       3782.00
         10.80       3726.00
         11.00       3688.00
         11.19       3642.00
         11.39       3584.00
         11.66       3512.00
         11.80       3398.00
         12.02       3322.00
         12.19       3222.00
         12.39       3145.00
         12.66       3098.00
         12.80       3144.00
         13.02       3134.00
         13.19       3137.00
         13.41       3175.00
         13.64       3152.00
         13.80       3095.00
         14.02       3062.00
         14.19       3046.00
         14.39       3010.00

I have a data set like above, I used 'trapz' command to calculate the area under the curve. Using that, we can calculate the total area. my question is can anybody help me to do the area under the curve calculation related to each time gap? if we can't use trapz command can we use the 'int' command?

Thanks in advance

Answer 1

[Torsten]

for k=1:length(T)-1
  area(k)=0.5*(Y(k)+Y(k+1))*(T(k+1)-T(k));
end

area(k) gives you the area under the graph between T(k) and T(k+1).

Best wishes

Torsten.