Thomas Andrews DDS weird behaviour

[rvg]

I am trying to use the "dds" command in Thomas Andrews' dealer program (http://bridge.thomasoandrews.com/deal/commands.html#ddscmd ) in order to compute the number of tricks declarer (north) can make in a Spade contract. The full hand is :

 

[hv=s=sak654h52dAK52cqj&n=sJ9832hTdj3cak732&w=sQhaj98763dq94cT8]400|300[/hv]

 

I am trying to figure out how many tricks declarer can make on the lead of the Ace of Heart from West's hand thus :

 

source format/none

set diagram { 
  {J9832 T J3 AK732}
  {T7 KQ4 T876 9654}
  {AK654 52 AK52 QJ}
  {Q AJ98763 Q94 T8}                                                                                           
}

set tricks [dds -leader west -diagram $diagram -trick AH south spades]                                                                                                                                                                                                                                           
puts "tricks on AH lead are $tricks (expected 12)"
set tricks [dds -leader west -diagram $diagram -trick AH south spades]
puts "tricks on AH lead are $tricks (expected 12)"                                                                                                                      

 

The strange behavior is that the first invocation of the dds returns the value of 0 whereas the second (identical) call to dds returns 12 (the correct answer). I was wondering if someone knew what I was doing wrong here.

 

u1347224@penguin:~/git/gdealer/deal319/linux$ ./deal  -i repro.tcl
tricks on AH lead are 0 (expected 12)
tricks on AH lead are 12 (expected 12)

[barmar]

I've moved this to the General Bridge Discussion forum, as DDS is not part of BBO.

[Mbodell]

I've experienced something similar in some instances where the first time a program is run things aren't initialized right and get 0. I solve it by re-running the command in the case that 0 is the answer.

[rvg]

Yes, I can reproduce this consistently - when dds is called the first time it returns a zero whenever second hand has a singleton