Frequency values extracted not commensurate with expectated values
Previously reported on github dttxml repo.
When extracting a transfer function from a DTT file using dttxml
, the frequency values do not match the ASCII exported values from DTT. Below is a print comparison
dttxml freq = 7.0; ASCII freq = 7.0
dttxml freq = 7.652900218963623; ASCII freq = 7.6529
dttxml freq = 8.366600036621094; ASCII freq = 8.3666
dttxml freq = 10.0; ASCII freq = 10.0
dttxml freq = 12.115300178527832; ASCII freq = 12.1153
dttxml freq = 14.678000450134277; ASCII freq = 14.678
dttxml freq = 15.600000381469727; ASCII freq = 15.6
dttxml freq = 16.399999618530273; ASCII freq = 16.4
dttxml freq = 17.100000381469727; ASCII freq = 17.1
dttxml freq = 17.600000381469727; ASCII freq = 17.6
dttxml freq = 19.100000381469727; ASCII freq = 19.1
dttxml freq = 21.544300079345703; ASCII freq = 21.5443
dttxml freq = 26.101600646972656; ASCII freq = 26.1016
dttxml freq = 31.622800827026367; ASCII freq = 31.6228
dttxml freq = 38.3119010925293; ASCII freq = 38.3119
dttxml freq = 46.41590118408203; ASCII freq = 46.4159
dttxml freq = 56.234100341796875; ASCII freq = 56.2341
dttxml freq = 68.12920379638672; ASCII freq = 68.1292
dttxml freq = 82.54000091552734; ASCII freq = 82.54
dttxml freq = 100.0; ASCII freq = 100.0
dttxml freq = 134.2239990234375; ASCII freq = 134.224
dttxml freq = 177.8280029296875; ASCII freq = 177.828
dttxml freq = 237.13699340820312; ASCII freq = 237.137
dttxml freq = 292.21099853515625; ASCII freq = 292.211
dttxml freq = 340.65399169921875; ASCII freq = 340.654
dttxml freq = 433.70001220703125; ASCII freq = 433.7
dttxml freq = 490.3269958496094; ASCII freq = 490.327
dttxml freq = 543.2130126953125; ASCII freq = 543.213
dttxml freq = 625.7420043945312; ASCII freq = 625.742
dttxml freq = 699.4650268554688; ASCII freq = 699.465
dttxml freq = 749.8939819335938; ASCII freq = 749.894
dttxml freq = 824.2650146484375; ASCII freq = 824.265
dttxml freq = 962.7639770507812; ASCII freq = 962.764
dttxml freq = 1221.5699462890625; ASCII freq = 1221.57
Note that some frequency offsets are 1/2^18. Not sure if that is a clue as to the origin of the differences, as they are much larger (and in some cases consistent with neighbors) than floating point errors
I am running dttxml-1.1.4 installed via pip with python-3.7. If I can provide any other details, just let me know.