| 1 | ### adj =====================================================================
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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 | m
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| 10 |
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| 11 | General description
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| 12 | -------------------
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| 13 | Returns the adjunct of matrix m. The inverse of m is equal to adj(m) divided by det(m).
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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_adj = ->
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| 19 | push(cadr(p1))
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| 20 | Eval()
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| 21 | adj()
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| 22 |
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| 23 | adj = ->
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| 24 | i = 0
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| 25 | j = 0
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| 26 | n = 0
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| 27 |
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| 28 | save()
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| 29 |
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| 30 | p1 = pop()
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| 31 |
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| 32 | if (istensor(p1) && p1.tensor.ndim == 2 && p1.tensor.dim[0] == p1.tensor.dim[1])
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| 33 | doNothing = 1
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| 34 | else
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| 35 | stop("adj: square matrix expected")
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| 36 |
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| 37 | n = p1.tensor.dim[0]
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| 38 |
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| 39 | p2 = alloc_tensor(n * n)
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| 40 |
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| 41 | p2.tensor.ndim = 2
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| 42 | p2.tensor.dim[0] = n
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| 43 | p2.tensor.dim[1] = n
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| 44 |
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| 45 | for i in [0...n]
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| 46 | for j in [0...n]
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| 47 | cofactor(p1, n, i, j)
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| 48 | p2.tensor.elem[n * j + i] = pop(); # transpose
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| 49 |
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| 50 | push(p2)
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| 51 |
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| 52 | restore()
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| 53 |
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| 54 |
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