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階乘到度數腳本

我很難在腳本內進行階乘，以便將某些 DOE 因子分配給某些階乘。

我可以使用 nchoosekMatrix() 來獲得第一個級別，但無法弄清楚如何動態獲得高於 1 的級別。

Names default to here(1);

factorial_to_degree = function({factors, degree = 2, termlist = {}}, 
	{DEFAULT LOCAL}, 
	if(degree!=1, 
		termlist = recurse(factors, degree-1, termlist);
	);
	nckmat = nchoosekmatrix(nrows(factors), degree);
	for(r = 1, r<=nrows(nckmat), r++, 
		AddTermExpr = Expr(AddTerm());
		for(c=1, c<=ncols(nckmat), c++, 
			insert into(AddTermExpr, Evallist({factors[nckmat[r, c]], 1}));
		);
		insert into(termlist, nameexpr(AddTermExpr));
	);
	return(termlist);
);

factorial_to_degree([1, 2, 3], 2);

//returns
/*
{AddTerm( {1, 1} ), AddTerm( {2, 1} ), AddTerm( {3, 1} ), AddTerm( {1, 1}, {2, 1} ),
AddTerm( {1, 1}, {3, 1} ), AddTerm( {2, 1}, {3, 1} )}
*/

//want it to return
/*
{
	AddTerm( {1, 1} ), AddTerm( {2, 1} ), AddTerm( {3, 1} ), 
	AddTerm( {1, 2} ), AddTerm( {2, 2} ), AddTerm( {3, 2} ),
	AddTerm( {1, 1}, {2, 1} ), AddTerm( {1, 1}, {3, 1} ), AddTerm( {2, 1}, {3, 1} )
}
*/

我認為我應該遞歸地做一些事情，但我很難真正讓任何事情發揮作用。

任何幫助將不勝感激。

實驗設計品質和工藝工程回复：階乘腳本

我意識到我的期望是不正確的。這實際上與擬合模型宏所做的相同。  

 

不過，我更喜歡以下迭代方法。  

 

factorial_to_degree = function({factors, degree}, 
 n_factors = nitems(factors);
 factors = shape(factors, n_factors);
 termlist = {};
 for(i=1, i<=degree, i++, 
  nckmat = nchoosekmatrix(n_factors, i);
  for(r = 1, r<=nrows(nckmat), r++, 
   AddTermExpr = Expr(AddTerm());
   for(c=1, c<=ncols(nckmat), c++, 
    insert into(AddTermExpr, Evallist({factors[nckmat[r, c]], 1}));
   );
   insert into(termlist, nameexpr(AddTermExpr));
  );
 );
 return(termlist);
);