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ListTools[Group] - group a list into an expression sequence of lists
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Calling Sequence
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Group(f, L, opts, ...)
Group[N](f, opt[1], ..., opt[N-1], L, opts, ...)
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Parameters
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L
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list
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f
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procedure
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N
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positive integer
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opts
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(optional) options to procedure f
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Description
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The Group(f, L) function groups list L into sublists where procedure f returns either true or false. The value of procedure f is determined by the expression  evaluated for each element x of list L.
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The Group(f, L, opts) function performs in a similar manner, except that the value of procedure f is determined by the expression  .
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If Group is indexed by a positive integer N, the expression ![f(opt[1], () .. (), opt[N-1], x, opts)](/support/helpjp/helpview.aspx?si=6749/file02064/math123.png) is evaluated for each list element x.
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Examples
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>
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>
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![L := [`$`(1 .. 10)]](/support/helpjp/helpview.aspx?si=6749/file02064/math138.png)
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![L := [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]](/support/helpjp/helpview.aspx?si=6749/file02064/math141.png)
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![[1], [2, 3], [4], [5], [6], [7], [8, 9, 10]](/support/helpjp/helpview.aspx?si=6749/file02064/math148.png)
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>
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![[1], [2], [3], [4], [5], [6], [7], [8], [9], [10]](/support/helpjp/helpview.aspx?si=6749/file02064/math155.png)
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| (4) |
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![Group(`>`, [seq(sin(2.0*x), x = 1 .. 12)], -1/2)](/support/helpjp/helpview.aspx?si=6749/file02064/math166.png)
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![[.90930], [-.75680], [-.27942, .98936], [-.54402, -.53657], [.99061, -.28790], [-.75099], [.91295, -0.88513e-2], [-.90558]](/support/helpjp/helpview.aspx?si=6749/file02064/math169.png)
| (5) |
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![Group(`@`(evalb, `>`), [seq(sin(2.0*x), x = 1 .. 12)], -1/2)](/support/helpjp/helpview.aspx?si=6749/file02064/math173.png)
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![[.90930], [-.75680], [-.27942, .98936], [-.54402, -.53657], [.99061, -.28790], [-.75099], [.91295, -0.88513e-2], [-.90558]](/support/helpjp/helpview.aspx?si=6749/file02064/math176.png)
| (6) |
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, x = 1 .. 12)], less_than)](/support/helpjp/helpview.aspx?si=6749/file02064/math180.png)
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![[sin(2)], [sin(4)], [sin(6), sin(8)], [sin(10), sin(12)], [sin(14), sin(16)], [sin(18)], [sin(20), sin(22)], [sin(24)]](/support/helpjp/helpview.aspx?si=6749/file02064/math183.png)
| (7) |
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