part(deg, f)
part(lo, hi, f)
part(deg, f)
part(lo, hi, wt, f)
part(mdeg, f)
part_deg f
To select terms of a single degree, use part(deg, f). An alternate syntax uses an underscore.
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To select terms within a range of degrees, use part(lo, hi, f).
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In the next example, we apply the weights \{2,3\} before selecting terms. In other words, the term x^ay^b is considered to have degree 2a+3b.
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If the generators of the ring were defined to have non-unit degrees, the weights override those degrees.
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By omitting lo or hi, but providing a comma indicating the omission, the range of degrees will be unbounded in the appropriate direction.
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Infinite numbers may also be given for the bounds.
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For multigraded rings, use a list to specify a single multidegree in the first argument. The underscore syntax works here too.
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A range of degrees cannot be asked for in the multigraded case. Polynomial rings over polynomial rings are multigraded, so either use a multidegree or specify weights to avoid errors.
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The object part is a method function.