q2=: (3 : 0)&((0&+) ::('invalid data type'"_))"1
if. ([: -. (3=#) *. (0~:{.)) y do. 'Not quadratic' return. end.
'A B C'=. y
SQRTD=. %: (*:B)- +:^:2 A*C
S=. SQRTD-B
T=. -SQRTD+B
R=. (S [`]@.(<&|) T)%+:A
R , C % R * A
)
(quad,:q2)_1e_10 2 0.0001 NB. quad is RDM monadic p. solution
2e10 _5e_5
2e10 _5e_5
Swapping left and right causes
(quad,:|.@qbad)_1e_10 2 0.0001
2e10 _5e_5
2.04709e10 _4.88498e_5
On 11/07/2015 07:00 AM, [email protected] wrote:
Date: Fri, 6 Nov 2015 17:18:34 -0600
From: Kip Murray<[email protected]>
To:"[email protected]" <[email protected]>
Subject: [Jprogramming] Quadratic formula
Message-ID:
<CAOfWorjaCT8UZTKi-+Z342WAu+YKg9MRNQFSJKXLqgB+=pd...@mail.gmail.com>
Content-Type: text/plain; charset=UTF-8
Most of us have heard of the quadratic formula
x = ( -b +or- %: (b^2 - 4ac) )/2a (roughly standard math notation)
for solving ax^2 + bx + c = 0 for x .
Your mission, should you decide to accept it, is to write a verb quad
that takes
vector a,b,c as argument, says ?Not quadratic? if a is 0 , and otherwise
uses the quadratic formula to find the values of x, reporting them in a
vector.
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