1. Re: Optimization (was Edom 2.02)

Oops!
redo from start

From: me
>So I did an experiment, with the following output:

     Okay, as you may have guessed, I pasted the output from the wrong
experiment, and drew the wrong conclusions.  This was the append test:

Time for 10 thousand iterations of append
Expression:
       Time in seconds
----------
seq1 = append( seq1, 3 ):
       0.010000
seq1[3] = append( seq1[3], 3 ):
       3.440053
seq1[seq2[3]] = append( seq1[seq2[3]], 3 ):
       3.380052
seq1[seq2[3]] = append( seq1[seq2[3]], seq2[3] ):
       3.370052
seq1[3][3] = append( seq1[3][3], 3 ):
       3.370052
seq1[seq2[3]][3] = append( seq1[seq2[3]][3], 3 ):
       3.390052
seq1[seq2[3]][seq2[3]] = append( seq1[seq2[3]][seq2[3]], 3 ):
       3.430053
temp = append( temp, 3 ) (same as last one above, but using temp):
       3.410052
temp = append( temp, 3 ) (same as last one, but with temp set outside loop):
       0.010000
-------------------

New conclusion:  It only takes 0.000001 second for a straight atomic append.
That's pretty darn fast, I think.  But even one level of subscription takes
about 340 times as long.  The complexity of the subscription doesn't seem to
matter much after that.  And using a temp variable doesn't help if it's
inside the loop because of the subscription time on the assignment, (the
other experiment).  But if it's outside the loop, it works a minor miracle.

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