Wednesday, January 27, 2010

Simplifying The Erdnase System of Cull Shuffling

To put it bluntly, Erdnase is a difficult read. The culling section is so confusing with all the unnecessary math and lack of spacing in the descriptions it can be quite intimidating to even someone that is very familiar with the concepts. I cannot count how many times I’ve read the technique, cards in hand, and performed the same line twice destroying my previous work. My goal in this essay is to simplify the Erdnase culling process by taking out the math and breaking down the steps to an elementary level. I use the same terminology from the culling of two to nine cards, so the reader can progress easily and have an elevated understanding of what is taking place.


One area many individuals have trouble with is discerning the difference between the top card and the first card mid-shuffle when the cards are split between the hands. Erdnase defines the difference between these two terms under the heading “Technical Terms” earlier in the book.


I replace using the term “first card” with “first drawn card” so the reader understands it is the first card drawn off the right hand packet, and replaced “top card” with “top card of left hand packet”


It may be a good idea for you to practice by turning the cards you want to cull face up. I suggest you place them in the example positions and attempt the steps using my given numbers before trying it from a random deck. They are correct- trust me.


To Cull Two Cards


We are going to start from the top although it may sound simple to some. There’s only two numbers you will have to remember:


A= Number of cards (from the top) before the first desired card

B= Number of cards in between (and including) the first and second card


Example: Sound confusing? It’s not I promise. Go get your deck, I’ll wait.


Ready? Okay, pull out two Queens and place them in the following order: Random card (or X card as I will call them later), Random card, Queen, Random card, Random card, Queen.


A would equal 2 because there are two cards before our first Queen

B would equal 4 because there are two cards inbetween our two Queens (which we are also counting)


Here are the steps to cull the Queens to the bottom of the deck:

1. Undercut approx. half, injog the first drawn card, shuffle off, cut to injog (this is just done to position the cards to be stacked on top of the right hand packet)

2. Run A

3. Injog first drawn card (count as number one) and run the rest of B

4. Outjog next drawn card and shuffle off

5. Undercut to outjog forming break at injog

6. Injog first drawn card (this number will never change, we are just positioning those queens together) throw to break, shuffle off

7. Cut to injog and throw on top


The only part of that sequence that is ever going to change is the numbers in A and B. So what if the Queens were positioned 8 and 4 as in Erdnase’s example?


A would equal 7 for the number of X cards before the first Queen

B would equal 5 because there are 3 cards separating our 2 Queens


All I have really done is eliminated the extra math by getting a better understanding of the placement of the cards. Once you feel comfortable with culling two cards, move onto the next section.


To Cull Three Cards


Want to cull three of a kind? Erdnase has you covered. Here’s what you will have to remember:


A= Number of cards (from the top) before the first desired card

B= Number of cards in between (and including) first and second card

C= Number of cards between the second and third desired card


Example: We have three Kings positioned every fourth card from the top. (X card, X card, X card, King, X Card, X Card, X Card, King, etc...) The numbers you would remember are:


A= 3

B= 5

C= 3


Here are your steps:

1. Undercut approx. half, injog the first drawn card, shuffle off, cut to injog

2. Run A

3. Injog first drawn card (count as number one) and run the rest of B

4. Outjog next drawn card (count as number one) and run rest of C

5. Throw remaining stack on top

6. Undercut to outjog forming break at injog

7. Injog top card of left hand packet, run one card (this number will never change), throw to break, and shuffle rest of stack on top

8. Cut to injog and throw on top


To Cull Four Cards


So let’s say you have the four Aces spotted near the top and you want to get them all together. Easy as pie. There will be four numbers (surprise!) to memorize.


A= Number of cards (from the top) before the first desired card

B= Number of cards in between (and including) first and second card

C= Number of cards between the second and third desired card

D= Number of cards between the third and fourth card


Example: Let’s assume the four aces are every third card from the top (as in: X card, X card, Ace, X card, X card, Ace, etc....). The numbers you would remember are:


A=2

B=4

C=2

D=2


Here are your steps:

1. Undercut approx. half, injog the first drawn card, shuffle off, cut to injog

2. Run A

3. Injog first drawn card (count as number one) and run the rest of B

4. Outjog next drawn card (count as number one) and run rest of C

5. Throw remaining stack on top

6. Undercut to outjog forming break at injog

7. Injog top card of left hand packet, run one card (this number will never change), throw to your break, and shuffle rest of stack on top

8. Undercut to injog and run D and throw on top


This will leave you with three Aces on bottom and one on top. Erdnase suggests alleviating this by simply running one card into the left hand and throwing the balance of the deck on top.


To Cull 9 Cards


If there was ever a part of Erdnase I was guilty of skipping, this would be it. Erdnase System of Cull Shuffling- To Cull Nine Cards


Even the title is intimidating. And I know what you’re thinking. Hey, I know how to cull 2, 3, and 4 cards, why the heck would I want to memorize all those numbers to cull 9 cards?


Well here’s the thing....


You are not culling 9 cards, you are culling 3 sets (or groups) of cards. Whether that be face cards, red/black cards, cards of a certain suit, or even face down cards in a face up deck- as long as they are in 3 groups you are good to go. You could even use this simple technique to cull 3 single cards! And you only have to remember 4 key numbers to execute it. Keep in mind this cull was optimally designed to cull cards that are already in 3 groups of 3 or more. I would suggest using this cull after a hearts or spades demonstration, where you have the suits already clumped together in the collected tricks.


Here’s all you need to memorize:


A= number of cards before first group

B= number from (and including) first desired card to last desired card of second group

C= number of cards between second and third group

D= number of cards in second group


Example: Let’s say we have 3 groups that each contain 3 Diamonds. There are two indifferent cards separating each group. (X card, X card, 3 Diamond cards, X card, X card, 3 Diamond cards, X card, X card, 3 Diamond cards) The numbers you would remember are:


A=2

B=8

C=2

D=3


Here are the steps (really broken down):


1. Undercut approx. half, injog the first drawn card, shuffle off, cut to injog

2. Run A

3. Injog first drawn card (count as number 1) and run the rest of B

4. Outjog next drawn card (count as number 1) and run rest of C

5. Throw remaining stack on top

6. Undercut to outjog and form a break at injog

7. Injog top card of left hand packet

8. Run D

9. Throw to break shuffle off

10. Cut to injog and throw on top


One little tidbit that’s going to confuse you when you practice this:


You are only going to get the first card of the last grouping on the bottom, the rest will be on top. If you want to have all the cards on the bottom, you just need to memorize a 5th number, the number of cards in the 3rd group, and run that number minus one (because you’ll already have one where you want it) from the top to the bottom after the previous 10 steps.

6 comments:

Martin said...

Thank God!!!
The Erdnase Cull Shuffling has been the bain of my existence since the first time I read it. By the way, if you are interested, I did create some math-like formulas that help me practice stock shuffling; I could create something similar to that for cull shuffling.

ChesspatzerESP said...

Great post. Thanks for trying to simplify this difficult subject!

I have coincidentally posted about the same topic today. You may want to have a look at: http://erdnase.exofire.net/blog/?p=32

By the way, it would be great if you contributed to the Forum.

Keep up the good work

J. Wessmiller said...

Martin- sure I am very interested. Feel free to e-mail me.

Martin said...

Sent! check your in box.

J. Wessmiller said...

very good stuff martin- thanks for sharing!

Anonymous said...

Might be the Most excellent subject that i read all year?