Dissimilar Tank Matching

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Much easier:

For a buddy team with dissimilar tank sizes the point is to derive a usable turn pressure for your own tank, AFTER calculating a normalized volume of Rock Bottom and/or Thirds for the teammate with the smallest tank. The arithmetic is fairly easy and straight forward (in metric of course):

Example:
12 litre/bar tank multiplied by an initial fill of 180 bar equals 2160 litres;
15 litre/bar tank multiplied by initial fill 150 bar equals 2250 litres --

Therefore the 12 litre tank has the smaller volume at 2160 litres.

Calculate thirds of smaller volume tank's fill pressure of 180 bar, and you get 60 bar delta turn pressure. 12 litres/bar multiplied by 60 bar equals 720 litres volume (this is the normalized value with respect to the smaller tank).

Hence , the calculated turn pressure for the larger volume tank is:
720 litres divided-by 15 litre/bar equals 48 bar.

(How objectively simple was that? And no App needed....)

:)
My eyes glazed over at the end of the word "example:"

That is why I wrote an app, I HATE math... besides whats this bar thing you speak of? Most divers in High Springs go to The Great Outdoors Restaurant after diving for the day.

:)

Tim
 
:)
My eyes glazed over at the end of the word "example:"

That is why I wrote an app, I HATE math... besides whats this bar thing you speak of? Most divers in High Springs go to The Great Outdoors Restaurant after diving for the day.

:)

Tim

I'm good at AND love math. What's funny is tbone's comment was pro-metric. He's starting to switch to bar and meters.....which is going to make diving with him fun if we ever decide to do that math (I'm feet and pounds).

Tim, I wrote a bunch of codes in Middle School and High School, and even a bunch through college, just to give me a more thorough understanding of what was going on behind the scenes. Programming the math in is much more involved than just regurgitating some formula because you have to know all of the variables and variants. It's a great way to learn it properly.
 
thank god for sidemount and independent gas planning :) or the fact that we're both engineers and can do the math in our heads, that's convenient too
 
I'm good at AND love math. What's funny is tbone's comment was pro-metric. He's starting to switch to bar and meters.....which is going to make diving with him fun if we ever decide to do that math (I'm feet and pounds).

Tim, I wrote a bunch of codes in Middle School and High School, and even a bunch through college, just to give me a more thorough understanding of what was going on behind the scenes. Programming the math in is much more involved than just regurgitating some formula because you have to know all of the variables and variants. It's a great way to learn it properly.
To learn a math function properly, you have to understand the underlying concept, formulae and algebraic & arithmetic operation manually, and rigorously practice writing out the method & solution with pencil & paper and calculator.

Computer programming & App writing in this instance (e.g. figuring out total gas consumption for a range of depths) is only an ancillary, convenient tool for iterative/looping processes & summing operations.
 
OH... so your saying I'm actually a math wizard :)

So I'm changing my story, I sucked at Algebra because my instructors didn't understand what they were teaching me. (probably closer to the truth, based on my last instructor actually looking into my brain and knowing why I was having such a hard time with it).

Tim
 
To learn a math function properly, you have to understand the underlying concept, formulae and algebraic & arithmetic operation manually, and rigorously practice writing out the method & solution with pencil & paper and calculator.

Computer programming & App writing in this instance (e.g. figuring out total gas consumption for a range of depths) is only an ancillary, convenient tool for iterative/looping processes & summing operations.

I've found that sometimes pencil and paper doesn't quite do it for me as it doesn't require the permutations that programming it does. Programming something is such a unique way of looking at the math that it adds some flavor and life to how you think about it and comprehend it. I've done a LOT of VERY advanced math and can say for certain that I've never not learned appreciably more by programming it than by simply doing it on pencil/paper. I'm not saying I do it in something like Matlab/Mathematica exclusively, but programming the functions is a new way of looking at things.

For example: Tim could've downloaded another program to do it for him and run it himself. That's not a great way of learning the math. Doing the math himself a few times on pencil and paper is a great way of learning it. However, programming a code that solves it for him is another great way of learning it because he has to dig in to the base equations more so than simply on pencil/paper.

Either way, way to go, Tim....would you say you have a better grasp of the math?
 
I don't think gas matching requires all that much math, or even aptitude for it. It requires some fundamental concepts about gas planning, and the only arithmetic (I won't even call it math) needed is how to convert PSI to volume (if you're not using the metric system) for the tanks you're using.

... it ain't rocket surgery ...

... Bob (Grateful Diver)
 
Either way, way to go, Tim....would you say you have a better grasp of the math?

:)
I had the math down after the first part of my Cave1 with Shirley.... however the math added a LOT of stress to the class and ultimately caused me to change instructors. At that point I knew I was going to put the process into an application for anyone else that was in need of verification (or just to lazy to do it after their class) because in the middle of a cave class is NOT the time to be freaking out about a stupid math problem. You should be stressed about the skills you are learning while underwater, NOT the underlying math above water.

Yes it is an easy concept when just dealing with any formula, but put the math skill inside of an already stressful dive class (if your not stressed in a tek class, something else is going on) and it just sort of blows up. Its just an additional stressor that does't need to be.

Tim
 
I'm good at AND love math. What's funny is tbone's comment was pro-metric. He's starting to switch to bar and meters.....which is going to make diving with him fun if we ever decide to do that math (I'm feet and pounds).

Tim, I wrote a bunch of codes in Middle School and High School, and even a bunch through college, just to give me a more thorough understanding of what was going on behind the scenes. Programming the math in is much more involved than just regurgitating some formula because you have to know all of the variables and variants. It's a great way to learn it properly.

I've found that sometimes pencil and paper doesn't quite do it for me as it doesn't require the permutations that programming it does. Programming something is such a unique way of looking at the math that it adds some flavor and life to how you think about it and comprehend it. I've done a LOT of VERY advanced math and can say for certain that I've never not learned appreciably more by programming it than by simply doing it on pencil/paper. I'm not saying I do it in something like Matlab/Mathematica exclusively, but programming the functions is a new way of looking at things.

For example: Tim could've downloaded another program to do it for him and run it himself. That's not a great way of learning the math. Doing the math himself a few times on pencil and paper is a great way of learning it. However, programming a code that solves it for him is another great way of learning it because he has to dig in to the base equations more so than simply on pencil/paper.

Either way, way to go, Tim....would you say you have a better grasp of the math?
First things first Vic . . . You have to understand the concept and rote method manually to effect a logically correct mathematical solution. And if you are well practiced & can do this above water with paper & pencil, you can do it just as well on wetnotes underwater at depth, if need be. . .
 
:)
I had the math down after the first part of my Cave1 with Shirley.... however the math added a LOT of stress to the class and ultimately caused me to change instructors. At that point I knew I was going to put the process into an application for anyone else that was in need of verification (or just to lazy to do it after their class) because in the middle of a cave class is NOT the time to be freaking out about a stupid math problem. You should be stressed about the skills you are learning while underwater, NOT the underlying math above water.

Yes it is an easy concept when just dealing with any formula, but put the math skill inside of an already stressful dive class (if your not stressed in a tek class, something else is going on) and it just sort of blows up. Its just an additional stressor that does't need to be.

Tim

you shouldn't be freaking out or stressed about anything in Cave 1..or Cave 2 for that matter. Pretty much every problem can be solved by calming yourself down and thinking it through (both the math and the in water skills).
 
https://www.shearwater.com/products/perdix-ai/
http://cavediveflorida.com/Rum_House.htm

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