The -- operator not working

The -- operator not working

Return to topic list

Thu Oct 11 05:05:23 2012   by   John A,
I am working on a program for a friend who has the need to find the probabilities of picking marbles from a bag.  The program below mostly does this except the 'drop' function in line 5 does not do what I wanted it to do.  I discovered the recent addition of the -- function.  However, simply replacing the drop function with -- does not work.  At least, it does not on variables representing sets.  Is this a bug or am I misunderstanding how -- works or is it just not implemented yet in the web app?

Thanks for the help,

John

A:=0; \\1 or 2 for 2nd or 3rd pick.
t:={1,2,2,2,2,3,3,3,3,3,3,4};\\The marbles 1 Crit 2 Hit 3 Miss 4 Fumble
u:=t pick A;
t:=t drop u;
t pick 1
 
Mon Oct 15 11:08:37 2012   by   Torben
I'm not sure what you want to accomplish, so I can't really see what goes wrong.  Could you explain what your roll should do?
 
Mon Oct 15 16:16:26 2012   by   John A
Hi Torben,

There is a bag of different colored marbles.  1 white, 1 Black, 6 red, 4 blue.  12 in all.  If you pick 3 marbles at a time, what is the probability that a a given set or even a given marble would be pulled?  It is sententially a 3 car draw.  The 'drop' function drops an entire type a given set.  The '--' only drops 1 piece which is what I want.

I should be able to simply replace the 'drop' function with the '--' function and it should work.  It does not with the web app.

John
 
Mon Oct 15 19:17:30 2012   by   John A
To put it another way this...

A:=0; \\1 or 2 for 2nd or 3rd pick.
t:={1,2,2,2,2,3,3,3,3,3,3,4};\\The marbles 1 Crit 2 Hit 3 Miss 4 Fumble
u:=t pick A;
t:=t drop u;
t pick 1

Works fine but this...

A:=0; \\1 or 2 for 2nd or 3rd pick.
t:={1,2,2,2,2,3,3,3,3,3,3,4};\\The marbles 1 Crit 2 Hit 3 Miss 4 Fumble
u:=t pick A;
t:=t -- u;
t pick 1

does not.  The affected line is line 5 of each piece of code.

Thanks,

John


 
Mon Oct 15 19:18:16 2012   by   Sorry...
Line 4 not line 5.
 
Mon Oct 15 19:18:56 2012   by   John A
Sorry...Line 4 not line 5.
 
Tue Oct 16 11:15:13 2012   by   Torben
I found the problem and fixed it.  It was a silly mistake: I had forgotten to add the -- operator to the code that expands assignments, so that was why it did not recognize the variable.
 

Return to topic list



New message:
Topic:
Posted by:

Type the values of the dice shown below:

Return to topic list