loops - Excel VBA - Work with Subgroup of Array -

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i have 1-dimensional array 1000 entries. loop through parts of array , apply calculate average on subgroup. have done far looks this:

        temp = array(myarray)          temp_range = application.index(temp, evaluate("row(1:10)"))          average(i) = application.average(temp_range)

by can calculate average of first 10 rows. not dynamic @ all, , wondering if there way of working subgroups of array (so can loop through them)?

thanks help, can't figure 1 out...

update: tried code here st.dev (not average). works! much. however, code slow. there way of making faster?

here loop: return array of 1000 returns. aim calculate standard deviation of 1 year of daily return data.

    = 2 n      if year(dates(i)) > year(dates(i - 1))          test = application.index(return, evaluate("row(" & c & ":" & (i - 2) & ")"))          vola(m) = application.stdev(test) * sqr(252)          m = m + 1         c = - 1      else          test = application.index(return, evaluate("row(" & c & ":" & (i - 1) & ")"))          on error resume next         vola(m) = application.stdev(test) * sqr(252)      end if  next

without knowing more how you're looping through these, could:

dim frstrow long, lstrow long  'within loop, assign values frstrow, lstrow  temp_range = application.index(temp, evaluate("row(" & frstrow & ":" & lstrow &")"))

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