How do I fold my function over a list?

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1

I have a feeling a need to use a variant of iterate however I’m
struggling to get the exact syntax. I have

gcd:{[x;y] $[0~y;:x;:gcd[y;x mod y]]; };
lcm:{[x;y] x*y%gcd[x;y]};
x: 1+ til 10

And I would like to fold lcm over x. Step by step
lcm [10;9] = 90
lcm [90;8] = 360
etc

2

To: personal-kdbplus@googlegroups.com
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> gcd:{[x;y] $[0~y;:x;:gcd[y;x mod y]]; };
> lcm:{[x;y] x*y%gcd[x;y]};
> x: 1+ til 10
>
> And I would like to fold lcm over x. Step by step
> lcm [10;9] = 90
> lcm [90;8] = 360
> etc

gcd:{$[y;gcd[y;x mod y];x]} / simplify
lcm:{x*y div gcd[x;y]} / fix 'type
x:1+til 10

over’s tricky sometimes

here’s how to work out the solution:

q)lcm[10;9]
90
q)lcm[lcm[10;9];8]
360
q)lcm[;8]lcm[10;9]
360
q)lcm[;8]lcm[;9]10
360
q)lcm over 10 9 8
360
q)lcm over reverse x
2520

(note that “reverse” isn’t actually useful in this particular case, =
since lcm is commutative, but that’s how to get that particular order)=