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InactiveRiemannSumToIntegral (2.0.0) current version: 3.0.0 »

Source Notebook

Determine an integral corresponding to a Riemann sum

Contributed by: Wolfram|Alpha Math Team

ResourceFunction["InactiveRiemannSumToIntegral"][fun,{i,1,n},nInfinity,x]

expresses the Riemann sum of fun over i from 1 to n as an integral in the variable x.

Examples

Basic Examples (1) 

Find the integral corresponding to the Riemann sum with summand :

In[1]:=
ResourceFunction["InactiveRiemannSumToIntegral"][(1 + i/n)/n, {i, n}, n -> Infinity, x]
Out[1]=

Scope (2) 

Find the integral corresponding to the Riemann sum with summand :

In[2]:=
ResourceFunction["InactiveRiemannSumToIntegral"][(i/n)/n, {i, n}, n -> Infinity, x]
Out[2]=

Find the integral corresponding to the Riemann sum with summand Cos[(1+i)/n]/n:

In[3]:=
ResourceFunction["InactiveRiemannSumToIntegral"][
 Cos[(1 + i)/n]/n, {i, n}, n -> Infinity, x]
Out[3]=

Possible Issues (1) 

If an integral could not be found, an inactivated form of the limit is returned with a message:

In[4]:=
ResourceFunction["InactiveRiemannSumToIntegral"][(i/n)/Cos[n], {i, n},
  n -> Infinity, x]
Out[4]=

Publisher

Wolfram|Alpha Math Team

Version History

  • 3.0.0 – 23 March 2023
  • 2.0.0 – 08 October 2021

Related Resources

Author Notes

To view the full source code for InactiveRiemannSumToIntegral, evaluate the following:

In[1]:=
SystemOpen[
 FileNameJoin[{DirectoryName[FindFile["ResourceFunctionHelpers`"]], "InactiveRiemannSumToIntegral.wl"}]]

License Information