Every time I read the headline for a fast algorithm for inverse square root I think "Well, yeah, you just multiply the input by itself. Can't get much faster to undo a square root than that." Silly me.
My native language isn't English, and I made the very same mistake like 50 times already. Sometimes I still forget what inverse means in math. I would instantly understand "reciprocal" though, which is the name I learnt for this operation.
>Sometimes I still forget what inverse means in math.
I think your interpretation is actually the more correct one, here.
Squaring and square-rooting are the inverse of each other.
They are really talking about calculating the reciprocal of the square root of X. They are calling it the 'inverse square root', but thats just them abusing terminology, which people do all the time, rightly or wrongly.
But you weren't wrong to be initially confused by this abuse of terminology, and it doesn't have anything to do with your native language not being English.
I thought the same thing. I guess the confusion comes from thinking of the inverse of the function square root instead of the multiplicative inverse of the value of the square root function. Technically I suppose the terminology is a bit hand-wavy, since you could have also been referring to the additive inverse, but I think it's fairly common to talk about "inverses" of members of a field and assume that people know you mean multiplicative inverses. But that's exactly what isn't a safe assumption here, since you could be thinking about a function (which seems like the more natural interpretation), as opposed to a number.
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Every time I read the headline for a fast algorithm for inverse square root I think "Well, yeah, you just multiply the input by itself. Can't get much faster to undo a square root than that." Silly me.
My native language isn't English, and I made the very same mistake like 50 times already. Sometimes I still forget what inverse means in math. I would instantly understand "reciprocal" though, which is the name I learnt for this operation.
>Sometimes I still forget what inverse means in math.
I think your interpretation is actually the more correct one, here. Squaring and square-rooting are the inverse of each other.
They are really talking about calculating the reciprocal of the square root of X. They are calling it the 'inverse square root', but thats just them abusing terminology, which people do all the time, rightly or wrongly.
But you weren't wrong to be initially confused by this abuse of terminology, and it doesn't have anything to do with your native language not being English.
I thought the same thing. I guess the confusion comes from thinking of the inverse of the function square root instead of the multiplicative inverse of the value of the square root function. Technically I suppose the terminology is a bit hand-wavy, since you could have also been referring to the additive inverse, but I think it's fairly common to talk about "inverses" of members of a field and assume that people know you mean multiplicative inverses. But that's exactly what isn't a safe assumption here, since you could be thinking about a function (which seems like the more natural interpretation), as opposed to a number.