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[mail-mi]

Log
Action-Treasure-Victory
If this is base e, +1 card, +1 action
If this is base 10, $1
If this is base 2, 1 VP

[ChocophileBenj]

Let's kill everything :

And yet all those logarithm functionsare only multiplications by a real number of the basic (base e) logarithm function.

For all x > 0, for all a >0, a != 1 : log_a(x) = ln(x)/ln(a), ln being the basic function.


-Mathematical venture-
Treasure, cost $0*
Worth 0*
When you play this, you may either stop here or reveal cards from your deck until you find a treasure. Discard the other revealed cards. Play that treasure. If all the treasures you played due to one Mathematical venture are worth more than $7, they are all worth $0. Otherwise, you may either stop here or repeat.

[Kirian]

Chemists use common log all the time, for pH, pKa, and spectroscopy.  We also use natural log sometimes.  Common log are also used in acoustics and acoustic engineering (decibels).  Other fields:

Geology: base sqrt(1000) for the Richter scale and mass moment scale
Astronomy: base 100^(1/5) for magnitude, because 2.511 is totally memorable or something, don't ask me
Music: base 2^(1/12) for a twelve-tone scale

With the exception of perhaps that music application, the others are just arbitrarily use base 10 by convention.  You could just as well you natural logarithms for something like pH or acoustics or the Richter scale.

Sure, we could, but we don't.  Just as mathematicians apparently don't use common logs ever.  Then again, the level of mathematician we're talking about here don't use actual numbers.

I know mathematicians like their purity; I understand the desire to put everything in base e.  But there are plenty of reasons for chemists to use common log for pH.  Mainly because Kw is close to 10^-14, and therefore [H+] is close to 10^-7 M.  pH is just a shortcut, but it's a meaningful one, not just arbitrary.

[SirPeebles]

If you consider real/complex numbers to be actual numbers (and I'm not sure that I do), then logarithms usually show up in areas of mathematics that deal with actual numbers.  Sure, the discrete log problem is a famous counterexample in cryptography, but that's, well, an edge case.

[Tables]

Far too much of mathematics involves annoying competing notational standards. Most of the time, it's just there's four ways of writing the same thing, some favoured by mathematicians, some by physicists, some by computer scientists and so on. But sometimes, you get discrepancies with things like log/lb/lg/ln, or other things (such as using the same letter to refer to two different things, and other more major ones that don't come to mind right now).

There's also the public understanding of the BIDMAS rule (You might use PIDMAS in the US, I guess, since you call parentheses what we call brackets), which people regularly get wrong (although the ambiguity could be removed easily using brackets). For example, what does 5-3+2 equal?

If you said 0 then you've fallen into the regular trap. The answer is actually 4. This is because the rule really means (B)(I)(DM)(AS), evaluating things in each bracket in the order they come, not explicitly addition before subtraction.

[Powerman]

Graduate School
Action $3P
+1 Card
+2 Actions
Gain a card costing up to $6

[WanderingWinder]

Far too much of mathematics involves annoying competing notational standards. Most of the time, it's just there's four ways of writing the same thing, some favoured by mathematicians, some by physicists, some by computer scientists and so on. But sometimes, you get discrepancies with things like log/lb/lg/ln, or other things (such as using the same letter to refer to two different things, and other more major ones that don't come to mind right now).

And what is your solution to this problem?
Relevant: http://xkcd.com/927/

There's also the public understanding of the BIDMAS rule (You might use PIDMAS in the US, I guess, since you call parentheses what we call brackets), which people regularly get wrong (although the ambiguity could be removed easily using brackets). For example, what does 5-3+2 equal?

If you said 0 then you've fallen into the regular trap. The answer is actually 4. This is because the rule really means (B)(I)(DM)(AS), evaluating things in each bracket in the order they come, not explicitly addition before subtraction.

It boggles my mind that people miss this. Again, how do you propose fixing this? Forcing brackets everywhere is clunky - and of course you can just include them everywhere anyway, nobody is stopping you. And forcing addition to be before subtraction suddenly means there is a potential difference in subtracting five and adding negative five, and this seems just *more* confusing to me.

It's not that the standards aren't arbitrary. They are (why do we use a right-hand coordinate system?). But there has to be *some* arbitrary standard.

[eHalcyon]

For the record, here in Canada we use BEDMAS as our mnemonic.  The E stands for Exponents.  B is for Brackets, even though we all know that they are properly called Parentheses.   It's just a mnemonic; we're taught that addition and subtraction are on the same level and we go left-to-right in that case.

[gman314]

For the record, here in Canada we use BEDMAS as our mnemonic.  The E stands for Exponents.  B is for Brackets, even though we all know that they are properly called Parentheses.   It's just a mnemonic; we're taught that addition and subtraction are on the same level and we go left-to-right in that case.

I'm also Canadian, and I did K-9 in a French Immersion school, where we used PEDMAS. I was mildly surprised, when Parentheses became Brackets in High School.

[eHalcyon]

For the record, here in Canada we use BEDMAS as our mnemonic.  The E stands for Exponents.  B is for Brackets, even though we all know that they are properly called Parentheses.   It's just a mnemonic; we're taught that addition and subtraction are on the same level and we go left-to-right in that case.

I'm also Canadian, and I did K-9 in a French Immersion school, where we used PEDMAS. I was mildly surprised, when Parentheses became Brackets in High School.

As I know them:

(parentheses)
[square brackets]
<angle brackets>
{braces}

[Axxle]

For the record, here in Canada we use BEDMAS as our mnemonic.  The E stands for Exponents.  B is for Brackets, even though we all know that they are properly called Parentheses.   It's just a mnemonic; we're taught that addition and subtraction are on the same level and we go left-to-right in that case.

I'm also Canadian, and I did K-9 in a French Immersion school, where we used PEDMAS. I was mildly surprised, when Parentheses became Brackets in High School.

As I know them:

(parentheses)
[square brackets]
<angle brackets>
{braces}

Function parameter containers
Array location
Templates
Code containers

[sudgy]

I never learned a mnemonic, I just learned that you do things in brackets/parenthesis first, then exponents, then multiplication/division, then addition/subtraction.

[mail-mi]

PEMDAS
$2
When you Play this card, gain an Estate.
If you have any Monuments in play when you play this, Discard this card.
+2 Actions
+$1
--
When you trash this card, gain a Silver.

[StrongRhino]

I learned it as PEMDAS as well.
Did the people getting it wrong not go to school?

[KingZog3]

I learned it as PEMDAS as well.
Did the people getting it wrong not go to school?

BEMDAS or BEDMAS. B or brackets.

[Kirian]

I learned it as PEMDAS as well.
Did the people getting it wrong not go to school?

There are multiple different mnemonics for it, which vary from country to country and region to region.  Way back when I learned it, it was Please Pardon My Dear Aunt Sally, with the second P obviously being for powers.

[SirPeebles]

[WanderingWinder]

See but the traditional resistor color one that I learned (and from different totally unrelated people) would actually work here: Bad Boys Rape Our Young Girls, But Violet Gives Willingly

[SirPeebles]

This may be why Randall qualifies "None" with "that I care for".

[eHalcyon]

His SI prefixes are missing some!  hecto, deca, deci, centi

[Kirian]

Why does anyone need a mnemonic for resistor color codes anyway?  They're in order by color already!

[Tables]

And what is your solution to this problem?

Mostly, there isn't a problem. Context is usually the solution. If you're going out of context, don't use log(x) without a base.

It boggles my mind that people miss this. Again, how do you propose fixing this? Forcing brackets everywhere is clunky - and of course you can just include them everywhere anyway, nobody is stopping you. And forcing addition to be before subtraction suddenly means there is a potential difference in subtracting five and adding negative five, and this seems just *more* confusing to me.

It's not that the standards aren't arbitrary. They are (why do we use a right-hand coordinate system?). But there has to be *some* arbitrary standard.

I never really liked the mnemonic. I think it confuses just as much as it helps. Fortunately, for most people, BIDMAS in strictly that order is acceptable for pretty much everything, and anything that would be potentially confusing in terms of addition and subtraction will generally be bracketed. The main place it isn't okay is for trick questions on facebook and the like. Anyone who needs to know the difference will probably understand the order of operations well enough anyway, so I don't think there's an issue.

Why does anyone need a mnemonic for resistor color codes anyway?  They're in order by color already!

Agreed. Black, Brown, Rainbow. That should be the mnemonic.

[WanderingWinder]

Why does anyone need a mnemonic for resistor color codes anyway?  They're in order by color already!

Colors aren't in order. Yes, you can go with wavelength, but then you need to know which end you're starting on, people need to actually know the wavelength order, and you still have brown, black, gray, and white which aren't covered by that. And that's 40% of the colors.

Of course, I can just remember it, but I don't expect other people to. The thing is, I can make the same case about any of those other mnemonics - all the others I just remember, except the geologic periods, which I don't think a mnemonic is going to help me on.

[Powerman]

Super Market
$7 Action
+2 Cards
+2 Actions
+2 Buys
+$2
__________
You can't buy this if you have any cards in play.

[Dsell]

Super Market
$7 Action
+2 Cards
+2 Actions
+2 Buys
+$2
__________
You can't buy this if you have any cards in play.

I'm loving mining village and death cart.