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Toom–Cook multiplication
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==== Faster evaluation ==== Multipoint evaluation can be obtained faster than with the above formulas. The number of elementary operations (addition/subtraction) can be reduced. The sequence given by Bodrato<ref name="Bodrato2007"/> for Toom-3, executed here over the first operand (polynomial ''p'') of the running example is the following: :{| |- |''p''<sub>0</sub> || ← || ''m''<sub>0</sub> + ''m''<sub>2</sub> || = || 56789012 + 123456 || = ||align="right"| 56912468 |- |''p''(0) || = || ''m''<sub>0</sub> || = || 56789012 || = ||align="right"| 56789012 |- |''p''(1) || = || ''p''<sub>0</sub> + ''m''<sub>1</sub> || = || 56912468 + 78901234 || = ||align="right"| 135813702 |- |''p''(−1) || = || ''p''<sub>0</sub> − ''m''<sub>1</sub> || = || 56912468 − 78901234 || = ||align="right"| −21988766 |- |''p''(−2) || = || (''p''(−1) + ''m''<sub>2</sub>) × 2 − ''m''<sub>0</sub> || = ||align="right"| (− 21988766 + 123456 ) × 2 − 56789012 || = || − 100519632 |- |''p''(∞) || = || ''m''<sub>2</sub> || = || 123456 || = ||align="right"| 123456. |} This sequence requires five addition/subtraction operations, one less than the straightforward evaluation. Moreover the multiplication by 4 in the calculation of ''p''(−2) was saved.
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