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/sci/ - Science & Math

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9759970 No.9759970 [Reply] [Original]

Is it true that chemists and biologists compute integrals by cutting out and weighting paper? Are you fucking kidding me? How do they take derivatives then?

https://www.youtube.com/watch?v=AAJyWGTjdqM

>> No.9760167

>>9759970
>Is it true that chemists and biologists compute integrals by cutting out and weighting paper?
no

>> No.9760190
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9760190

>>9759970
>Is it true that chemists and biologists compute integrals by cutting out and weighting paper?
yes

>> No.9760203

>>9760190
Nice work, you clipped out the relevant part

>> No.9760212

>>9760203
The information in the "relevant part" can be found in any calc 1 textbook

>> No.9760259

>>9759970
it's true

i computed a gaussian integral using nothing but 1m^2 cardboard. my precision cutting skills got me within 0.01% of the actual value

this is the future of calculus, accept it.

>> No.9760283

>>9759970
I'm curious, why would you want to weigh paper to find the area under the curve instead of just evaluating the integral like a normal person?

>> No.9760288

>>9760283
Many times with biological there is no well defined expression representing the data and so an analytical solution is not possible.

Also nobody actually does the paper thing anymore, they just numerically integrate.

>> No.9760307

>>9760288
Makes sense. Just seems extremely autistic and silly.

>> No.9760654

Let's see this guy integrate over an 8 dimensional vector space with paper

>> No.9761282

>>9759970
This did in fact happen
Because it was simply much easier in those days were computers weren't as prevalent to cut out the area and weigh the paper instead of finding fit functions for every conceivable peak in your nmr spectrum and then doing the integrations
it sounds ridiculous, but it's actually not that surprising (and it's actually a thing chemists make fun of at this point)

>> No.9761297

>>9760307
Trying to find an integral is autistic?

>> No.9761539

>>9760212
I'm pretty sure the methods are relevant if you're trying to make a point.

>> No.9761678

>>9759970
not anymore
maybe somewhere in Pakistan where they can't afford new GC machines
>>9760283
because it takes like 1 minute no matter how oddly misshaped a peak is and we have very precise scales around

>> No.9761774

>>9759970
I'm a physicist and I did this as part of my curiculum.
The measurement apparatus was so old you only got the result on paper.
We still called it the chemist's integral though.

>> No.9761879

seems like an elegant and smart way to do it when you have no adequate alternatives.

>> No.9762313

>the virgin computation vs the chad approximation