Table of Contents generated with DocToc
Table of Contents generated with DocToc
hollerith-codec
Binary encoding for Hollerith that provides a total ordering for primitive datatypes and lists of those. Used by Hollerith and KWIC.
Breaking Change in v2.x: Prior to v2.x, when comparing two lists a, b where a is a prefix of b
used to be sorted with a first, then b, i.o.w. a shorter word always precedes a longer word that starts
out the same (as in an alphabetically sorted dictionary).
Starting with v2, however, this has been changed such that when comparing two lists a, b where a is a
prefix of b, b will be sorted before a if the first 'extra' element of b (i.e. b[ a.length ]) is
a negative number. By way of example, sorting now looks like this (with hexadecimal byte values):
[ -10, ] ... 4b bfdbffffffffffff 4c
[ -1, ] ... 4b c00fffffffffffff 4c
[ ] ... 4c
[ 0, ] ... 4d 0000000000000000 4c
[ 1, -1, ] ... 4d 3ff0000000000000 4b c00fffffffffffff 4c
[ 1, ] ... 4d 3ff0000000000000 4c
[ 1, 0, ] ... 4d 3ff0000000000000 4d 0000000000000000 4c
[ 1, 1, ] ... 4d 3ff0000000000000 4d 3ff0000000000000 4c
[ 10, -2, ] ... 4d 4024000000000000 4b bfffffffffffffff 4c
[ 10, -2, 3, ] ... 4d 4024000000000000 4b bfffffffffffffff 4d 4008000000000000 4c
[ 10, -1, ] ... 4d 4024000000000000 4b c00fffffffffffff 4c
[ 10, -1, 3, ] ... 4d 4024000000000000 4b c00fffffffffffff 4d 4008000000000000 4c
[ 10, ] ... 4d 4024000000000000 4c
[ 10, 0, ] ... 4d 4024000000000000 4d 0000000000000000 4c
[ 10, 0, 3, ] ... 4d 4024000000000000 4d 0000000000000000 4d 4008000000000000 4c
[ 10, 1, ] ... 4d 4024000000000000 4d 3ff0000000000000 4c
[ 10, 1, 3, ] ... 4d 4024000000000000 4d 3ff0000000000000 4d 4008000000000000 4c
[ 10, 2, ] ... 4d 4024000000000000 4d 4000000000000000 4c
[ 10, 2, 3, ] ... 4d 4024000000000000 4d 4000000000000000 4d 4008000000000000 4c
[ 10, 4, -2, ] ... 4d 4024000000000000 4d 4010000000000000 4b bfffffffffffffff 4c
[ 10, 4, -1, ] ... 4d 4024000000000000 4d 4010000000000000 4b c00fffffffffffff 4c
[ 10, 4, ] ... 4d 4024000000000000 4d 4010000000000000 4c
[ 10, 4, 0, ] ... 4d 4024000000000000 4d 4010000000000000 4d 0000000000000000 4c
[ 10, 4, 1, ] ... 4d 4024000000000000 4d 4010000000000000 4d 3ff0000000000000 4c
[ 10, 4, 2, ] ... 4d 4024000000000000 4d 4010000000000000 4d 4000000000000000 4c
Benchmarks
Sample run:
hollerith_tng 0.235 s 300,000 items 1,274,500⏶Hz 785⏷nspc
hollerith_bcd 2.543 s 300,000 items 117,963⏶Hz 8,477⏷nspc
hollerith_classic 7.113 s 300,000 items 42,176⏶Hz 23,710⏷nspc
Averages:
00:56 HENGIST/BENCHMARKS ▶ hollerith_tng 1,248,369 Hz ≙ 1 ÷ 1.0 100.0 % │████████████▌│
00:56 HENGIST/BENCHMARKS ▶ hollerith_bcd 118,161 Hz ≙ 1 ÷ 10.6 9.5 % │█▏ │
00:56 HENGIST/BENCHMARKS ▶ hollerith_classic 42,056 Hz ≙ 1 ÷ 29.7 3.4 % │▍ │
