title: how to calculate Riemann Sums in R?
body: <p>Can any one help how to find approximate area under the curve using Riemann Sums in R?</p>
  
  <p>It seems we do not have any package in R which could help.</p>
  
  <p>Sample data:</p>
  
  <pre><code>MNo1    X1  Y1    MNo2  X2  Y2
  1   2981    -66287  1   595 -47797
  1   2981    -66287  1   595 -47797
  2   2973    -66087  2   541 -47597
  2   2973    -66087  2   541 -47597
  3   2963    -65887  3   485 -47397
  3   2963    -65887  3   485 -47397
  4   2952    -65687  4   430 -47197
  4   2952    -65687  4   430 -47197
  5   2942    -65486  5   375 -46998
  5   2942    -65486  5   375 -46998
  6   2935    -65286  6   322 -46798
  6   2935    -65286  6   322 -46798
  7   2932    -65086  7   270 -46598
  7   2932    -65086  7   270 -46598
  8   2936    -64886  8   222 -46398
  8   2936    -64886  8   222 -46398
  9   2948    -64685  9   176 -46198
  9   2948    -64685  9   176 -46198
  10  2968    -64485  10  135 -45999
  10  2968    -64485  10  135 -45999
  11  2998    -64284  11  97  -45799
  11  2998    -64284  11  97  -45799
  12  3035    -64084  12  65  -45599
  12  3035    -64084  12  65  -45599
  13  3077    -63883  13  37  -45399
  13  3077    -63883  13  37  -45399
  14  3122    -63683  14  14  -45199
  14  3122    -63683  14  14  -45199
  15  3168    -63482  15  -5  -44999
  15  3168    -63482  15  -5  -44999
  16  3212    -63282  16  -20 -44799
  16  3212    -63282  16  -20 -44799
  17  3250    -63081  17  -31 -44599
  17  3250    -63081  17  -31 -44599
  18  3280    -62881  18  -38 -44399
  18  3280    -62881  18  -38 -44399
  19  3301    -62680  19  -43 -44199
  19  3301    -62680  19  -43 -44199
  20  3313    -62480  20  -45 -43999
  </code></pre>