%%HP: T(3)A(D)F(.);
\<< { { "CONT"
  \<< CONT
  \>> } } TMENU
"Old X1,Y1?" PROMPT
'Y1' STO 'X1' STO
"Old X2,Y2?" PROMPT
Y1 - SWAP X1 - SWAP
R\->P SWAP NEG '\Ga'
STO "New X1,Y1?"
PROMPT 'Y3' STO
'X3' STO
"New X2,Y2?" PROMPT
Y3 - SWAP X3 - SWAP
R\->P SWAP '\Ga' STO+ -
ABS .001 > 0 MENU
  IF
  THEN
"Scale is not the same"
DOERR
  END
\>>
