Here's my (primitive) work out in J
of generating primitive Pythagorean triples (ppt) based on
http://mathworld.wolfram.com/PythagoreanTriple.html
Generator matrices
U=: 1 2 2 , _2 _1 _2 ,: 2 2 3
A=: 1 2 2 , 2 1 2 ,: 2 2 3
D=: _1 _2 _2 , 2 1 2 ,: 2 2 3
Starting ppt
mada=: 3 4 5
Limiting expression for selecting primitives,
in this case only ppt's with hypotenuse < 100
flim =: 100 > {:
dot =: +/ . *
gppt =: 3 : 0
M =. y
r =. ,: mada
ppt =. mada dot M
while. flim ppt do.
r=. r , ppt
ppt =. {: r dot M
end.
}. r
)
Array of ppts:
ppts=: mada, (gppt U) , (gppt D), (gppt A)
No doubt there's a more J-ish way in doing this,
especially for gppt ??!!
greetings,
@@i=arie
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