Tacitly...
(A=. 0&{) (B=. 1&{) (C=. 2&{)
0&{ 1&{ 2&{
qr=. (-@:B + (+ , -) @:%:@:(*:@:B - 4 * A * C)) % 2 * A
quad=. qr`('Not quadratic'"_)@.(0 -: A) f.
quad 2 _8 6
3 1
quad 0 _8 6
Not quadratic
On Mon, Nov 9, 2015 at 2:26 AM, Don Kelly <[email protected]> wrote:
> If you assume the form is ax^2 +bx +c =0 then all you have to do is check
> for a=0
> 0=0{ a b c is true so not quadratic and flag it if true
>
> Don Kelly
>
>
> On 11/6/2015 3:18 PM, Kip Murray wrote:
>
>> 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.
>>
>> quad 2 _8 6
>> 3 1
>>
>> quad 0 _8 6
>> Not quadratic
>>
>> --Kip Murray
>>
>>
>>
>>
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