| 1 | ### denominator =====================================================================
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| 2 |
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| 3 | Tags
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| 4 | ----
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| 5 | scripting, JS, internal, treenode, general concept
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| 6 |
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| 7 | Parameters
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| 8 | ----------
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| 9 | x
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| 10 |
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| 11 | General description
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| 12 | -------------------
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| 13 | Returns the denominator of expression x.
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| 14 |
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| 15 | ###
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| 16 |
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| 17 |
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| 18 | Eval_denominator = ->
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| 19 | push(cadr(p1))
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| 20 | Eval()
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| 21 | denominator()
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| 22 |
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| 23 | denominator = ->
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| 24 | h = 0
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| 25 |
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| 26 | save()
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| 27 |
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| 28 | p1 = pop()
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| 29 |
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| 30 | if (car(p1) == symbol(ADD))
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| 31 | push(p1)
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| 32 | rationalize()
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| 33 | p1 = pop()
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| 34 |
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| 35 | if (car(p1) == symbol(MULTIPLY))
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| 36 | h = tos
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| 37 | p1 = cdr(p1)
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| 38 | while (iscons(p1))
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| 39 | push(car(p1))
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| 40 | denominator()
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| 41 | p1 = cdr(p1)
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| 42 | multiply_all(tos - h)
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| 43 | else if (isrational(p1))
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| 44 | push(p1)
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| 45 | mp_denominator()
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| 46 | else if (car(p1) == symbol(POWER) && isnegativeterm(caddr(p1)))
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| 47 | push(p1)
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| 48 | reciprocate()
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| 49 | else
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| 50 | push(one)
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| 51 |
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| 52 | restore()
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| 53 |
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