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Full Version: Blockmatrix
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Blockmat(2,3, {A,B,C,D,E,F})--> [A B C; D E F]
Blockmat(3,2, {A,B,C,D,E,F})--> [A B; C D; E F]
Blockmat(1,6, {A,B,C,D,E,F})--> [A B C D E F]
A, B, C, D, E, F are matrices of equal dimensions.
Code:
``` #cas Blockmat(n,p,lst):= BEGIN local j,k,c,d,m3,m2; IF ((n*p)<>size(lst)) THEN RETURN("matrices sizes"); END m2:=[]; m3:=[]; L0:={}; if p==1 then Blockmat1();return(m2); end; for k from 1 to n do IF k==1 THEN  for j from 1 to p do L0(j):=lst(j); end; m2:=trn(concat(L0)); c:=p;  ELSE L0:={}; d:=1; for j from c+1 to k*p do L0(d):=lst(j); d:=d+1; end; c:=k*p; m3:=trn(concat(L0)); m2:=concat(m2,m3); END; end; return(trn(m2)); END; #end #cas Blockmat1() BEGIN LOCAL j; L0:={}; B:=0; [A,B]:=DIM(lst(1)); for j from 1 to (size(lst)-1) do IF (DIM((lst(j)))<>DIM((lst(j+1)))) THEN kill; END; end; for j from 1 to (size(lst)) do L0:=concat(L0,mat2list(lst(j))); end; IF B==0 THEN m2:=(list2mat(L0,colDim(lst(1)))); ELSE m2:=(list2mat(L0,B)); END; END; #end```
Isn't there already a command that does this (list2mat)?
if matrix A= [1 2; 3 4] and B =[5 6; 7 8]
to block A and B into 2*1 is C=[A;B]=[1 2; 3 4;5 6;7 8]
list2mat will block it to C=[[A],[B]]=[[1 2; 3 4];[5 6; 7 8]] with extra brackets

if you have matrices A,B,C,D to be block into 2*2 matrix
A,B need to augmented, C ,D need to augmented---> CONCAT in hp prime
then the first has to stack on the later---> no STACK in hp prime;
that's what my code does...
I see now; this little program is quite useful.
Reference URL's
• HP Forums: https://www.hpmuseum.org/forum/index.php
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