solutionfromID

Class: FunctionApproximation.LUTSolution
Namespace: FunctionApproximation

Access a solution found during the approximation process

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Syntax

other_solution = solutionfromID(solution,id)

Description

other_solution = solutionfromID(solution,id) returns the solution associated with the FunctionApproximation.LUTSolution object, solution, with the ID specified by id.

Input Arguments

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The solution object containing the solution you want to explore, specified as a FunctionApproximation.LUTSolution object.

ID of the solution that you want to explore, specified as a scalar integer.

Data Types: double

Output Arguments

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FunctionApproximation.LUTSolution object associated with the specified ID.

Examples

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Open Live Script

This example shows how to use the solutionfromID method of the FunctionApproximation.LUTSolution object to examine other approximation solutions.

Create a FunctionApproximation.Problem object defining a math function to approximate. Then use the solve method to get a FunctionApproximation.LUTSolution object.

problem = FunctionApproximation.Problem('sin')
problem = 
  1×1 FunctionApproximation.Problem with properties:

    FunctionToApproximate: @(x)sin(x)
           NumberOfInputs: 1
               InputTypes: "numerictype(0,16,13)"
         InputLowerBounds: 0
         InputUpperBounds: 6.2832
               OutputType: "numerictype(1,16,14)"
                  Options: [1×1 FunctionApproximation.Options]


solution = solve(problem)
Searching for fixed-point solutions.

|  ID |  Memory (bits) | Feasible | Table Size | Breakpoints WLs | TableData WL | BreakpointSpecification |             Error(Max,Current) | 
|   0 |             64 |        0 |          2 |              16 |           16 |             EvenSpacing |     7.812500e-03, 1.000000e+00 |
|   1 |            784 |        1 |         47 |              16 |           16 |             EvenSpacing |     7.812500e-03, 5.388912e-03 |
|   2 |            768 |        1 |         46 |              16 |           16 |             EvenSpacing |     7.812500e-03, 4.534419e-03 |
|   3 |            608 |        1 |         36 |              16 |           16 |             EvenSpacing |     7.812500e-03, 4.089765e-03 |
|   4 |            592 |        1 |         35 |              16 |           16 |             EvenSpacing |     7.812500e-03, 4.272461e-03 |
|   5 |            416 |        1 |         24 |              16 |           16 |             EvenSpacing |     7.812500e-03, 6.201693e-03 |
|   6 |            400 |        1 |         23 |              16 |           16 |             EvenSpacing |     7.812500e-03, 6.958889e-03 |
|   7 |            224 |        0 |         12 |              16 |           16 |             EvenSpacing |     7.812500e-03, 4.013411e-02 |
|   8 |            304 |        0 |         17 |              16 |           16 |             EvenSpacing |     7.812500e-03, 1.887217e-02 |
|   9 |            352 |        1 |         20 |              16 |           16 |             EvenSpacing |     7.812500e-03, 7.807773e-03 |
|  10 |            320 |        0 |         18 |              16 |           16 |             EvenSpacing |     7.812500e-03, 1.695679e-02 |
|  11 |            336 |        1 |         19 |              16 |           16 |             EvenSpacing |     7.812500e-03, 7.810061e-03 |
|  12 |             64 |        0 |          2 |              16 |           16 |         EvenPow2Spacing |     7.812500e-03, 1.315166e+00 |
|  13 |            576 |        1 |         18 |              16 |           16 |          ExplicitValues |     7.812500e-03, 7.803448e-03 |
|  14 |            512 |        0 |         16 |              16 |           16 |          ExplicitValues |     7.812500e-03, 1.190175e-02 |
|  15 |            576 |        1 |         18 |              16 |           16 |          ExplicitValues |     7.812500e-03, 7.803448e-03 |

Best Solution
|  ID |  Memory (bits) | Feasible | Table Size | Breakpoints WLs | TableData WL | BreakpointSpecification |             Error(Max,Current) |
|  11 |            336 |        1 |         19 |              16 |           16 |             EvenSpacing |     7.812500e-03, 7.810061e-03 |

solution = 
  1×1 FunctionApproximation.LUTSolution with properties:

          ID: 11
    Feasible: "true"

Display all feasible solutions found during the approximation process.

displayfeasiblesolutions(solution)
|  ID |  Memory (bits) | Feasible | Table Size | Breakpoints WLs | TableData WL | BreakpointSpecification |             Error(Max,Current) | 
|   1 |            784 |        1 |         47 |              16 |           16 |             EvenSpacing |     7.812500e-03, 5.388912e-03 |
|   2 |            768 |        1 |         46 |              16 |           16 |             EvenSpacing |     7.812500e-03, 4.534419e-03 |
|   3 |            608 |        1 |         36 |              16 |           16 |             EvenSpacing |     7.812500e-03, 4.089765e-03 |
|   4 |            592 |        1 |         35 |              16 |           16 |             EvenSpacing |     7.812500e-03, 4.272461e-03 |
|   5 |            416 |        1 |         24 |              16 |           16 |             EvenSpacing |     7.812500e-03, 6.201693e-03 |
|   6 |            400 |        1 |         23 |              16 |           16 |             EvenSpacing |     7.812500e-03, 6.958889e-03 |
|   9 |            352 |        1 |         20 |              16 |           16 |             EvenSpacing |     7.812500e-03, 7.807773e-03 |
|  11 |            336 |        1 |         19 |              16 |           16 |             EvenSpacing |     7.812500e-03, 7.810061e-03 |
|  13 |            576 |        1 |         18 |              16 |           16 |          ExplicitValues |     7.812500e-03, 7.803448e-03 |
|  15 |            576 |        1 |         18 |              16 |           16 |          ExplicitValues |     7.812500e-03, 7.803448e-03 |

Best Solution
|  ID |  Memory (bits) | Feasible | Table Size | Breakpoints WLs | TableData WL | BreakpointSpecification |             Error(Max,Current) |
|  11 |            336 |        1 |         19 |              16 |           16 |             EvenSpacing |     7.812500e-03, 7.810061e-03 |

Solution with ID 5 is not listed as a feasible solution in the table. Explore this solution to see why it is not feasible.

solution5 = solutionfromID(solution, 5)
solution5 = 
  1×1 FunctionApproximation.LUTSolution with properties:

          ID: 5
    Feasible: "true"

Compare the numerical behavior of the solution with ID 5.

compare(solution5)

Figure contains 2 axes objects. Axes object 1 with title Comparison of Original Function and Approximation, xlabel Input, ylabel Function Value contains 2 objects of type line. These objects represent Original, Approximation. Axes object 2 with title Feasibility of Solution: Feasible AbsTol = 0.0078125 RelTol = 0.0078125, xlabel Input, ylabel Error contains 3 objects of type area, line. These objects represent Feasible Region : Absolute Error <= Max Error Allowed, Max Error Allowed : max(abs(Original) * RelTol, AbsTol), Absolute Error : abs(Original - Approximation).

ans = struct with fields:
    Breakpoints: [51473×1 double]
       Original: [51473×1 double]
    Approximate: [51473×1 double]

You can see from the plot that the solution does not meet the required tolerances.

Version History

Introduced in R2018a

See Also

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