US 12,141,021 B2
Programmatic selection of breakpoints and table values for a lookup table that conforms with an error tolerance
Yifu Zhang, Natick, MA (US); and Yuan Yuan, Natick, MA (US)
Assigned to The MathWorks, Inc., Natick, MA (US)
Filed by The MathWorks, Inc., Natick, MA (US)
Filed on Jan. 12, 2023, as Appl. No. 18/153,713.
Application 18/153,713 is a continuation in part of application No. 17/210,613, filed on Mar. 24, 2021, granted, now 11,579,956.
Claims priority of provisional application 63/386,827, filed on Dec. 9, 2022.
Claims priority of provisional application 63/386,630, filed on Dec. 8, 2022.
Claims priority of provisional application 63/123,122, filed on Dec. 9, 2020.
Prior Publication US 2023/0153185 A1, May 18, 2023
Int. Cl. G06F 9/44 (2018.01); G06F 11/07 (2006.01); G06F 11/36 (2006.01)
CPC G06F 11/0754 (2013.01) [G06F 11/3608 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method performed by a processor of an electronic device, comprising:
with the processor,
determining a next breakpoint for a lookup table that approximates a function or set of data values and produces output values based on input values, wherein the next breakpoint lies between a most recently established breakpoint in a breakpoint sequence and a breakpoint candidate positioned at a smallest input value of the lookup table among positions of breakpoint candidates;
wherein the breakpoint sequence extends from a breakpoint positioned at a largest input value of the lookup table among the positions of the breakpoints to a breakpoint positioned at a smallest input value of the lookup table among the positions of the breakpoints;
determining an associated table value for the next breakpoint in the lookup table, wherein the next breakpoint is determined by:
identifying breakpoint candidates that lie between the most recently established breakpoint and a breakpoint candidate with a position at a smallest input value of the lookup table among the positions of the breakpoint candidates;
determining associated table values for the identified breakpoint candidates;
choosing as the next breakpoint from the identified breakpoint candidates a breakpoint candidate that:
is in a subset of selected breakpoint candidates where, for each of the selected breakpoint candidates, an error function value of an output data value of the lookup table for each test point in an interval extending between the most recently established breakpoint and the selected breakpoint candidate is less than an error threshold, and
is a breakpoint candidate positioned at a smallest input value of the lookup table among positions of the selected breakpoint candidates in the subset; and
generating at least a portion of the lookup table with the most recently established breakpoint, the associated table value for the most recently established breakpoint, the next breakpoint, and the determined table value for the next breakpoint.