challenge HP50G RPL

[compsystems]

(09-24-2016 07:36 AM)Joe Horn Wrote:  How about two instructions?
« →V3 PROOT »

« →V3 PROOT » 'QUADRATIC1' STO

1. -3. 2. QUADRATIC1 returns [1, 2] // ok
1. 2. 3. QUADRATIC1 returns [(-1.,1.41421356238) (-1., -1.41421356238)] // ok
'A' 'B' 'C' QUADRATIC1 returns "→V3 ERROR" =(

with local vars & 8 instructions

Code:

« 
  → 
  A 
  B 
  C 
  '(-B+√(B^2-4*A*C))/(2*A)' EVAL 
  '(-B-√(B^2-4*A*C))/(2*A)' EVAL  
»
'QUADRATIC0' STO

with 12 instructions

Code:

«
  'R1(A,B,C)=(-B+√(B^2-4*A*C))/(2*A)' DEFINE
  'R2(A,B,C)=(-B-√(B^2-4*A*C))/(2*A)' DEFINE
  3 DUPN R1 EVAL 4 ROLLD R2 EVAL
» 
'QUADRATIC2' STO

/!\ First value, different from zero
1. -3. 2. QUADRATIC2 returns 1 2 // ok
1. 2. 3. QUADRATIC2 returns (-1.,1.41421356238) (-1., -1.41421356238) // ok
(1,0) (-1,-1) (0,1) QUADRATIC2 returns (1, 0) (0, 1)
'a' 'b' 'c' QUADRATIC2 EVAL returns
'(-b+√(c*-4.*a+SQ(b)))/(a*2.)'
'(-b-√(c*-4.*a+SQ(b)))/(a*2.)'


/!\ but the idea is to use the formula '-B±√(B^2-4*A*C)/2*A' with RPN commands (SWAP DUP ROLL ROLLD etc), also without unused local variables or globales and EVAL as in the first post


with the code of firts post
... 'QUADRATIC' STO
1. -3. 2. QUADRATIC returns 1 2 // ok
1. 2. 3. QUADRATIC returns (-1.,1.41421356238) (-1., -1.41421356238) // ok
(1,0) (-1,-1) (0,1) QUADRATIC returns (1, 0) (0, 1)
'a' 'b' 'c' QUADRATIC returns
'(-b+√(c*-4.*a+SQ(b)))/(a*2.)'
'(-b-√(c*-4.*a+SQ(b)))/(a*2.)'



PD: Someone who can port it to RPN HP-PRIME

Thanks