You know for the last week I've been rereading the 1st edition books and well I came across something that stumped me. For anyone who's spent any real time on my deviantart account will know I have a thing for size alteration, so of course the enlarge spell, the Expansion, and Reduction psionic disciplines are my jam. Obviously, calculating increases in size by % for the enlarge spell is easy, but then I realize that trying the opposite for level 610 magicuser is ... difficult so difficult in fact, I realized that trying to math out the exact final size is impossible in standard so I went straight to metric and well... First using my own height as the base for calculating all changes I switched my 75 inches to cm = 190.5. Ok, that parts easy then I thought, "well when I figured out how much i'd increased I multiply the base value by the % 190.5 * 200% (or 2.00) = 381 which you then add to the base value to get the your height after increased which is 571.5 or 18'9"," so I thought maybe I should divide it... which would just halve it, so that doesn't work. Then I thought maybe I should take into account the decimals and move them over for the .00, but that makes it 1.905 cm which 1% of the base size. Then I thought maybe rather than use the % maybe I should convert the % into a fraction since I am trying to find basically what the 1% of a 200% decrease in size is. so I took 190.5 and divided it by 1/200th by that just gave me a ridiculously huge whole number with no decimals which is definitively not correct, so I'm like I guess I should have multiplied then. So I multiplied the 190.5 instead and came out with .9525 cm or 9.525 mm, but that doesn't seem correct to me so I multipled it by 200% to see if I get 190.5 again. Instead it just doubles it, however if I multiple it by just 200 (which I think is what I am suppose to do when checking fractions) it comes out correct, but it still doesn't seem correct to me.
SO I gotta ask any of you know how you are suppose to handle more than 100% decreases in calculations, is .9525 cm actual what someone reduced by 200% would be, why does standard suck so hard at doing its job, is this why 2nd edition and oriental adventures used a flat rate size change instead of percentages? This ramble has been brought to you by the letter ?, "we exist to make think".
The science of Diminishing magic
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 Leema Har'gachi
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The science of Diminishing magic
CODENAME:Leema
Real Name:Leema Apollyon Har'gachi
Class:Variant Illusionist Favored Soul {gestalt}
Race:Shadow Drow
Height:5'8"
Weight:158 Ib.
Hair:Yellowish
Eyes:Purple(pinwheel)
Skin:Pitchblack(surrounded by Shadowy Purple Aura)
Deity:Eilistraee
Real Name:Leema Apollyon Har'gachi
Class:Variant Illusionist Favored Soul {gestalt}
Race:Shadow Drow
Height:5'8"
Weight:158 Ib.
Hair:Yellowish
Eyes:Purple(pinwheel)
Skin:Pitchblack(surrounded by Shadowy Purple Aura)
Deity:Eilistraee

 Demigod
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Re: The science of Diminishing magic
A 100 percent decease eliminates entire thing 11=0
In pure math a 200 percent decease results in a negative of amount that you start with. 1  (2 X 1) = 1
At best for your question after enlarge used, maybe consider as starting size as base. That once enlarged 100 percent, the enlarged target is considered 200 percent. That number you can reduce 200 percent by subtracting. At least without resulting in less than nothing.
While it is possible to increase by any percentage, it is impossible to decease any object more than 100 percent.
In pure math a 200 percent decease results in a negative of amount that you start with. 1  (2 X 1) = 1
At best for your question after enlarge used, maybe consider as starting size as base. That once enlarged 100 percent, the enlarged target is considered 200 percent. That number you can reduce 200 percent by subtracting. At least without resulting in less than nothing.
While it is possible to increase by any percentage, it is impossible to decease any object more than 100 percent.
 Leema Har'gachi
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Re: The science of Diminishing magic
Ok I've read this response several times to make sure I understand, so what it is you are saying (again, if I understand the second paragraph proper) is that figure out 100 percent change which would be 0. cm or actually .999999 (continuous 9) cm because there isn't actually a true 0 in measurements which could be simplified to just .9 (since we would have to ignore rounding for this to work) then... um ok, I think I over think'd your explanation?Bhaern Quel wrote: ↑Fri May 01, 2020 12:30 pmA 100 percent decease eliminates entire thing 11=0
In pure math a 200 percent decease results in a negative of amount that you start with. 1  (2 X 1) = 1
At best for your question after enlarge used, maybe consider as starting size as base. That once enlarged 100 percent, the enlarged target is considered 200 percent. That number you can reduce 200 percent by subtracting. At least without resulting in less than nothing.
While it is possible to increase by any percentage, it is impossible to decease any object more than 100 percent.
CODENAME:Leema
Real Name:Leema Apollyon Har'gachi
Class:Variant Illusionist Favored Soul {gestalt}
Race:Shadow Drow
Height:5'8"
Weight:158 Ib.
Hair:Yellowish
Eyes:Purple(pinwheel)
Skin:Pitchblack(surrounded by Shadowy Purple Aura)
Deity:Eilistraee
Real Name:Leema Apollyon Har'gachi
Class:Variant Illusionist Favored Soul {gestalt}
Race:Shadow Drow
Height:5'8"
Weight:158 Ib.
Hair:Yellowish
Eyes:Purple(pinwheel)
Skin:Pitchblack(surrounded by Shadowy Purple Aura)
Deity:Eilistraee
 Leema Har'gachi
 Traveler
 Posts: 135
 Joined: Sun Feb 10, 2013 2:19 am
 Location: Currently Off Realms
 Contact:
Re: The science of Diminishing magic
Ok, ok! I think I've figured out how Gygax wanted us to calculate the reverse of enlarge's reduction of size. First as stated in the posts above you can't use percentages to calculate how small you'd have to convert those percentages to fraction, in order to do this we have to do two things one is state your base size as a fraction which is the easy part unaffected by the spell you are 100/100th or 1/1. The second thing we need to do is to state the formula we import our fractions into which is base height (in inches or cm) * (top of fraction / bottom of fraction), this will always always equal your height  (your height * percent) for 20%, 40%, 60%, 80% so you can ignore using the fractions for those percents if you want, but the fraction is the only way to handle 100%, 120%, 140%, 160%, 180%, and 200%. Also, in order to be as accurate as possible you will need to have a calculator handy for these fractions or you will not get an accurate result. So I will start by subtracting the percent by the top fraction of your base height i.8 20 100 =80 so at 1st level the fraction you are reduced to is 80/100th and you then subtract the new top number for each of the next three levels 60/100th at 2nd level, 40/100th at 3rd level, and 20/100th at 4th level, however as stated in the posts above in measurements there is no such thing as as zero so for the last subtraction the fraction can only be reduced to 1/100th at 5th level.
Now you might think, "how are you going to to get the percents higher than 100 you've already reduce them as far as fraction will allow," and you would be wrong it just in order to figure out how much we shrink to by 120% or more we add rather then subtract, but to the bottom fraction this time. This actually get you the same rate and is equal ratio to the percentage increase of the enlarge spell, it just took me freak'in forever to figure that out. so you take or fraction 1/100 and add 20 to the bottom fraction for each level past 5th, so it 1/120th at 6th level, 1/140th at 7th level, 1/160th at 8th level, 1/180th at 9th level, and finally a maximum of 1/200th at 10th level.
So for example using my height (converted to Cm for accuracy's sake) 190.5 cm * (80/100 which equals .8[] ) would reduce me to 152.4 cm or 5 foot at 1st level, then to 114.3 cm or 3 feet 9 inches at 2nd, then to 76.2 cm or 2 feet 6 inches at 3rd level, then to 38.1 cm or 1 foot 2 inches at 4th level, then to 1.905 cm (19.05 mm) or 7.5 of an inch at 5th level, 1.5875 cm (15.875 mm) or 6.25 of an inch at 6th level, then to 1.3607 cm (13.607 mm) or 5.357 of an inch at 7th level, then to 1.1906 cm (11.906 mm) or 4.687 of an inch at 8th level, then to 1.0583 cm (10.583 mm) or 4.166 of an inch at 9th level, and then to a maximum diminshment of .9525 cm (9.525 mm) or 3.75 of an inch at 10th level. So I think I got it figured out finally.
Hey did you guys know that in the unearthed Arcana and the player character sheet book release a year after it changes the name of enlarge's reverse from reduce to diminish, I didn't really notice it until I read it more closely. I wonder what that change was about?
Now you might think, "how are you going to to get the percents higher than 100 you've already reduce them as far as fraction will allow," and you would be wrong it just in order to figure out how much we shrink to by 120% or more we add rather then subtract, but to the bottom fraction this time. This actually get you the same rate and is equal ratio to the percentage increase of the enlarge spell, it just took me freak'in forever to figure that out. so you take or fraction 1/100 and add 20 to the bottom fraction for each level past 5th, so it 1/120th at 6th level, 1/140th at 7th level, 1/160th at 8th level, 1/180th at 9th level, and finally a maximum of 1/200th at 10th level.
So for example using my height (converted to Cm for accuracy's sake) 190.5 cm * (80/100 which equals .8[] ) would reduce me to 152.4 cm or 5 foot at 1st level, then to 114.3 cm or 3 feet 9 inches at 2nd, then to 76.2 cm or 2 feet 6 inches at 3rd level, then to 38.1 cm or 1 foot 2 inches at 4th level, then to 1.905 cm (19.05 mm) or 7.5 of an inch at 5th level, 1.5875 cm (15.875 mm) or 6.25 of an inch at 6th level, then to 1.3607 cm (13.607 mm) or 5.357 of an inch at 7th level, then to 1.1906 cm (11.906 mm) or 4.687 of an inch at 8th level, then to 1.0583 cm (10.583 mm) or 4.166 of an inch at 9th level, and then to a maximum diminshment of .9525 cm (9.525 mm) or 3.75 of an inch at 10th level. So I think I got it figured out finally.
Hey did you guys know that in the unearthed Arcana and the player character sheet book release a year after it changes the name of enlarge's reverse from reduce to diminish, I didn't really notice it until I read it more closely. I wonder what that change was about?
CODENAME:Leema
Real Name:Leema Apollyon Har'gachi
Class:Variant Illusionist Favored Soul {gestalt}
Race:Shadow Drow
Height:5'8"
Weight:158 Ib.
Hair:Yellowish
Eyes:Purple(pinwheel)
Skin:Pitchblack(surrounded by Shadowy Purple Aura)
Deity:Eilistraee
Real Name:Leema Apollyon Har'gachi
Class:Variant Illusionist Favored Soul {gestalt}
Race:Shadow Drow
Height:5'8"
Weight:158 Ib.
Hair:Yellowish
Eyes:Purple(pinwheel)
Skin:Pitchblack(surrounded by Shadowy Purple Aura)
Deity:Eilistraee