[This message was posted by Michael Wong of Chi-X Global Technology <[email protected]> to the "FAST Protocol" discussion forum at http://fixprotocol.org/discuss/46. You can reply to it on-line at http://fixprotocol.org/discuss/read/93107a4f - PLEASE DO NOT REPLY BY MAIL.]
Rolf, I am sorry I got confused again. For tag 271, the pmap bit is 0. so the default value 0 is used for exponent. Can we say that the exponent has a value so that we need to decode mantissa? If so, the encoded value is 0x82 for the mantissa. The decoded value should be 1 since it is delta operator, Right? BTW, if the length field of a sequence field is greater than 1 , does the sequnce pmap appear each iteration? Michael > Michael, > > The pmap entry for the length field is located in the _message_ level > pmap (bit 7 in this case). The sequence level pmap occurs for every > iteration (repetition) of the sequence and provides presence info for > the fields in the current iteration. > > 271 should indeed be 2 (exponent=0). > > The FIX output would have been helpful earlier. Please provide a more > complete description of your problem if you want any more help. > > Good luck with your development. > > /Rolf > > > Rolf, > > > > First, since the length field has an operator, does it occupy the > > first bit of sequence PMAP? if so, I would like to know why pmap bit 5 > > is for 271. > > > > For 271, exponent=0(not -2) (copy not default) mantissa=2 => 2*10^0 = > > 2 the operator of exponent is copy. In this situation, PMAP bit is 0, > > use the initial value, so exp. = 0, right? If the value is not present > > in the stream and the state is undefined, then use the intial value. > > If the value is present and is null value, the field is absent if it > > is optional i.e. do not use the initial value. Am I right? > > > > BTW, this is the output for the first msg provided by swx 8=FIXT.1.1 35=X > > 1128=7 49=SWXGROUP-MDI.M01 56=SWXGROUP- > > MDC 34=10576 97=N 52=20080623- > > 03:55:01.9 1021=1 268=1 279=0 269=0 48=CH0003671440 22=4 271=2 273=03- > > :45:00.003 336=ABQ5 346=1 6566=0 83=1 > > > > Michael > > > > > > > Michael, > > > > > > your decoding up to 270 looks alright if I have understood the > > > context correctly. > > > > > > For 271 (field 5 in the sequence), pmap bit 5 is 0 so the wire > > > representation 0x82 corresponds to: exponent=-2 (default) mantissa=2 > > > => 2*10^-2? > > > > > > 270=NULL followed by 271=2*10^-2 don't make much sense though? > > > > > > I suggest you contact SWX for assistance on this. Let us know what > > > they say. > > > > > > Best, Rolf > > > > > > > Rolf, > > > > > > > > The previous message can be decoded successfully after you told me > > > > the sequence field PMAP. However, I have another messege that I > > > > fail to decode it > > > > > > > > msg (block size field is omitted): > > > > > > > > F7 01 C8 53 57 58 47 52 4F 55 50 2D 4D 44 49 2E 4D 30 B1 52 D0 32 > > > > 30 30 38 30 36 32 33 2D 30 33 3A 35 35 3A 30 31 2E 37 39 B9 81 81 > > > > 1B B0 43 48 30 30 30 33 36 37 31 34 34 B0 80 82 30 33 3A 34 35 3A > > > > 30 30 2E 30 30 B3 41 42 51 B5 81 FF 80 80 40 B0 02 AC 32 30 30 38 > > > > 30 36 32 33 2D 30 33 3A 34 35 3A 30 30 2E 30 30 B3 82 C5 01 C8 38 > > > > 30 B0 82 14 88 39 37 37 31 39 B3 82 80 81 81 81 A0 B1 FF 81 81 C0 > > > > 02 AC C1 01 C8 81 34 88 B0 36 32 32 37 36 31 B2 81 98 81 81 81 C0 > > > > 02 AC C0 01 C8 14 88 37 31 38 36 39 38 B1 82 E8 81 81 81 C0 02 AC > > > > C5 01 C8 B1 82 18 88 31 30 35 37 30 37 35 B9 81 03 CB AF 81 81 81 > > > > A0 B1 A0 A5 81 81 81 81 18 88 4C 49 30 30 31 30 37 33 37 32 31 B6 > > > > 82 7C B0 C4 81 81 81 85 B4 82 38 88 B0 43 48 30 30 30 39 36 39 31 > > > > 36 30 B8 80 EB 84 81 81 A4 B1 81 FF FD 81 C0 02 AC C0 01 C8 3C 88 > > > > B0 31 31 31 37 38 32 35 B5 81 00 F7 82 00 C8 81 81 81 A0 B1 8D 01 > > > > B4 81 81 81 81 3C 88 B0 36 39 33 36 30 B0 82 7E FB 81 7E 82 81 81 > > > > 81 80 18 88 34 38 34 30 36 B7 80 81 81 81 81 C0 02 AC C0 01 C8 14 > > > > 88 32 33 33 37 34 32 B1 83 FF 81 81 81 C0 02 AC C0 01 C8 3C 88 B1 > > > > 35 35 34 B0 81 93 82 00 FC 81 81 81 80 3C 88 B0 35 38 33 34 30 B4 > > > > 80 84 7F BB 82 81 81 C0 02 AC C0 01 C8 1C 88 32 37 31 36 38 B7 82 > > > > FC 83 CA FF > > > > > > > > PMAP = F7 (1 1110111) TID = 01 C8 49 = 53 57 58 47 52 4F 55 50 2D > > > > 4D 44 49 2E 4D 30 B1 34 = 52 D0 52 = 32 30 30 38 30 36 32 33 2D 30 > > > > 33 3A 35 35 3A 30 31 2E 37 39 B9 1021 = 81 268 = 81 Seq PMAP = 1B > > > > B0 (0011011 1 0110000) 48 = 43 48 30 30 30 33 36 37 31 34 34 B0 > > > > 270 = 80 271 = 82 ? > > > > > > > > I don't know how to proceed after tag 270. Template > > > > http://www.2shared.com/file/5736462/b9436b42/template1.html > > > > > > > > Thanks Michael > > > > > Michael, > > > > > > > > > > the length field occupies a bit in the message pmap if there is > > > > > an operator specified for the length field of the sequence. > > > > > > > > > > I don't have the FAST spec in front of me but IIRC section 6.2.5 > > > > > contains info about sequences. > > > > > > > > > > I can check more closely if you send me the template you are > > > > > using. > > > > > > > > > > /Rolf > > > > > > > > > > > Rolf, > > > > > > > > > > > > I want to know if the first bit of PMAP for sequence field > > > > > > indicate the presence of length field or not. Is there related > > > > > > information in the spec? > > > > > > > > > > > > Thanks Michael [You can unsubscribe from this discussion group by sending a message to mailto:[email protected]] --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Financial Information eXchange" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/FIX-Protocol?hl=en -~----------~----~----~----~------~----~------~--~---
