theorem
proved
harmonic_strict_mono
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IndisputableMonolith.CrossDomain.DFTHarmonicSpectrum on GitHub at line 102.
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99 linarith
100
101/-- Strict monotonicity of the comb. -/
102theorem harmonic_strict_mono (j k : DFTMode) (hjk : j.val < k.val) :
103 harmonicFrequency j < harmonicFrequency k := by
104 unfold harmonicFrequency
105 apply div_lt_div_of_pos_right _ (by norm_num : (8 : ℝ) > 0)
106 apply mul_lt_mul_of_pos_right _ phi_pos
107 · exact mul_lt_mul_of_pos_right (Nat.cast_lt.mpr hjk) (by norm_num)
108
109structure DFTHarmonicSpectrumCert where
110 modes_eight : Fintype.card DFTMode = 8
111 carrier_in_theta_band : 8 < carrierFreq ∧ carrierFreq < 8.1
112 all_modes_nonneg : ∀ k : DFTMode, 0 ≤ harmonicFrequency k
113 mode_zero_dc : harmonicFrequency ⟨0, by decide⟩ = 0
114 mode_seven_under_9 : harmonicFrequency ⟨7, by decide⟩ < 9
115 comb_monotone : ∀ j k : DFTMode, j.val < k.val →
116 harmonicFrequency j < harmonicFrequency k
117
118noncomputable def dftHarmonicSpectrumCert : DFTHarmonicSpectrumCert where
119 modes_eight := dftMode_count
120 carrier_in_theta_band := ⟨carrier_gt_8, carrier_lt_8point1⟩
121 all_modes_nonneg := harmonics_nonneg
122 mode_zero_dc := mode_zero
123 mode_seven_under_9 := mode_seven_lt_9
124 comb_monotone := harmonic_strict_mono
125
126end IndisputableMonolith.CrossDomain.DFTHarmonicSpectrum