The SUM Function

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The SUM Function

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The SUM function produces the sum of repetitive terms.  The form is:


value = SUM( name, initial, final, expression )


The expression argument is evaluated and summed for name = initial, initial+1, initial+2,


For example, the statement:


source = SUM(i,1,10,exp(-i))


forms the sum of the exponentials exp(-1)+exp(-2)+...+exp(-10).



The SUM function may be used with data ARRAYs, as in



   A = ARRAY(1,2,3,4,5,6,7,8,9,10)

   source = SUM(i,1,10,A[i])



Samples | Usage | Sum.pde