57 lines
2.0 KiB
Python
Executable File
57 lines
2.0 KiB
Python
Executable File
#!/usr/bin/env python3
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from math import pi, sin, cos, exp
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from numpy import arange
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from collections import namedtuple
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Result = namedtuple("Result", ["p1", "p2", "error"])
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def main():
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# f(x) = p1 * cos(p2 * x)
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parameter_cos_1=0.3
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parameter_cos_2=1.5
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transition_point = (1/parameter_cos_2) * pi/2 * 0.65
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cos_value = parameter_cos_1 * cos(parameter_cos_2 * transition_point)
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derived_cos_value = parameter_cos_1 * parameter_cos_2 * -sin(parameter_cos_2 * transition_point)
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#g(x) = e^(p1 - p2 * x)
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result = Result(10, 10, 1)
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step = 10
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while (result.error > 0.0001):
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parameter_ex_p1 = list(arange(result.p1 - step, result.p1 + step, step/10))
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parameter_ex_p2 = list(arange(result.p2 - step, result.p2 + step, step/100))
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step /= 10
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result = calculate(parameter_ex_p1, parameter_ex_p2, transition_point, cos_value, derived_cos_value)
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print("cos p1: " + str(parameter_cos_1))
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print("cos p2: " + str(parameter_cos_2))
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print("transition point: " + str(transition_point))
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print("p1: " + str(result.p1))
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print("p2: " + str(result.p2))
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print("combined error: " + str(result.error))
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def calculate(parameter_ex_p1, parameter_ex_p2, transition_point, cos_value, derived_cos_value):
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best_parameter_ex_p1 = -1
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best_parameter_ex_p2 = -1
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best_combined_error = 100
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for p1 in parameter_ex_p1:
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for p2 in parameter_ex_p2:
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value = exp(p1 - p2 * transition_point)
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derived_value = - p2 * exp(p1 - p2 * transition_point)
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error = abs(value - cos_value)
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derived_error = abs(derived_value - derived_cos_value)
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combined_error = error + derived_error
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if combined_error < best_combined_error:
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best_parameter_ex_p1 = p1
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best_parameter_ex_p2 = p2
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best_combined_error = combined_error
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return Result(best_parameter_ex_p1, best_parameter_ex_p2, best_combined_error)
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if __name__ == "__main__":
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main()
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