MPE Home Metamath Proof Explorer < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  MPE Home  >  Th. List  >  cshfn Structured version   Visualization version   GIF version

Theorem cshfn 13745
Description: Perform a cyclical shift for a function over a half-open range of nonnegative integers. (Contributed by AV, 20-May-2018.) (Revised by AV, 17-Nov-2018.)
Assertion
Ref Expression
cshfn ((𝑊 ∈ {𝑓 ∣ ∃𝑙 ∈ ℕ0 𝑓 Fn (0..^𝑙)} ∧ 𝑁 ∈ ℤ) → (𝑊 cyclShift 𝑁) = if(𝑊 = ∅, ∅, ((𝑊 substr ⟨(𝑁 mod (♯‘𝑊)), (♯‘𝑊)⟩) ++ (𝑊 substr ⟨0, (𝑁 mod (♯‘𝑊))⟩))))
Distinct variable group:   𝑓,𝑙
Allowed substitution hints:   𝑁(𝑓,𝑙)   𝑊(𝑓,𝑙)

Proof of Theorem cshfn
Dummy variables 𝑛 𝑤 are mutually distinct and distinct from all other variables.
StepHypRef Expression
1 eqeq1 2775 . . . 4 (𝑤 = 𝑊 → (𝑤 = ∅ ↔ 𝑊 = ∅))
21adantr 466 . . 3 ((𝑤 = 𝑊𝑛 = 𝑁) → (𝑤 = ∅ ↔ 𝑊 = ∅))
3 simpl 468 . . . . 5 ((𝑤 = 𝑊𝑛 = 𝑁) → 𝑤 = 𝑊)
4 simpr 471 . . . . . . 7 ((𝑤 = 𝑊𝑛 = 𝑁) → 𝑛 = 𝑁)
5 fveq2 6332 . . . . . . . 8 (𝑤 = 𝑊 → (♯‘𝑤) = (♯‘𝑊))
65adantr 466 . . . . . . 7 ((𝑤 = 𝑊𝑛 = 𝑁) → (♯‘𝑤) = (♯‘𝑊))
74, 6oveq12d 6811 . . . . . 6 ((𝑤 = 𝑊𝑛 = 𝑁) → (𝑛 mod (♯‘𝑤)) = (𝑁 mod (♯‘𝑊)))
87, 6opeq12d 4547 . . . . 5 ((𝑤 = 𝑊𝑛 = 𝑁) → ⟨(𝑛 mod (♯‘𝑤)), (♯‘𝑤)⟩ = ⟨(𝑁 mod (♯‘𝑊)), (♯‘𝑊)⟩)
93, 8oveq12d 6811 . . . 4 ((𝑤 = 𝑊𝑛 = 𝑁) → (𝑤 substr ⟨(𝑛 mod (♯‘𝑤)), (♯‘𝑤)⟩) = (𝑊 substr ⟨(𝑁 mod (♯‘𝑊)), (♯‘𝑊)⟩))
107opeq2d 4546 . . . . 5 ((𝑤 = 𝑊𝑛 = 𝑁) → ⟨0, (𝑛 mod (♯‘𝑤))⟩ = ⟨0, (𝑁 mod (♯‘𝑊))⟩)
113, 10oveq12d 6811 . . . 4 ((𝑤 = 𝑊𝑛 = 𝑁) → (𝑤 substr ⟨0, (𝑛 mod (♯‘𝑤))⟩) = (𝑊 substr ⟨0, (𝑁 mod (♯‘𝑊))⟩))
129, 11oveq12d 6811 . . 3 ((𝑤 = 𝑊𝑛 = 𝑁) → ((𝑤 substr ⟨(𝑛 mod (♯‘𝑤)), (♯‘𝑤)⟩) ++ (𝑤 substr ⟨0, (𝑛 mod (♯‘𝑤))⟩)) = ((𝑊 substr ⟨(𝑁 mod (♯‘𝑊)), (♯‘𝑊)⟩) ++ (𝑊 substr ⟨0, (𝑁 mod (♯‘𝑊))⟩)))
132, 12ifbieq2d 4250 . 2 ((𝑤 = 𝑊𝑛 = 𝑁) → if(𝑤 = ∅, ∅, ((𝑤 substr ⟨(𝑛 mod (♯‘𝑤)), (♯‘𝑤)⟩) ++ (𝑤 substr ⟨0, (𝑛 mod (♯‘𝑤))⟩))) = if(𝑊 = ∅, ∅, ((𝑊 substr ⟨(𝑁 mod (♯‘𝑊)), (♯‘𝑊)⟩) ++ (𝑊 substr ⟨0, (𝑁 mod (♯‘𝑊))⟩))))
14 df-csh 13744 . 2 cyclShift = (𝑤 ∈ {𝑓 ∣ ∃𝑙 ∈ ℕ0 𝑓 Fn (0..^𝑙)}, 𝑛 ∈ ℤ ↦ if(𝑤 = ∅, ∅, ((𝑤 substr ⟨(𝑛 mod (♯‘𝑤)), (♯‘𝑤)⟩) ++ (𝑤 substr ⟨0, (𝑛 mod (♯‘𝑤))⟩))))
15 0ex 4924 . . 3 ∅ ∈ V
16 ovex 6823 . . 3 ((𝑊 substr ⟨(𝑁 mod (♯‘𝑊)), (♯‘𝑊)⟩) ++ (𝑊 substr ⟨0, (𝑁 mod (♯‘𝑊))⟩)) ∈ V
1715, 16ifex 4295 . 2 if(𝑊 = ∅, ∅, ((𝑊 substr ⟨(𝑁 mod (♯‘𝑊)), (♯‘𝑊)⟩) ++ (𝑊 substr ⟨0, (𝑁 mod (♯‘𝑊))⟩))) ∈ V
1813, 14, 17ovmpt2a 6938 1 ((𝑊 ∈ {𝑓 ∣ ∃𝑙 ∈ ℕ0 𝑓 Fn (0..^𝑙)} ∧ 𝑁 ∈ ℤ) → (𝑊 cyclShift 𝑁) = if(𝑊 = ∅, ∅, ((𝑊 substr ⟨(𝑁 mod (♯‘𝑊)), (♯‘𝑊)⟩) ++ (𝑊 substr ⟨0, (𝑁 mod (♯‘𝑊))⟩))))
Colors of variables: wff setvar class
Syntax hints:  wi 4  wb 196  wa 382   = wceq 1631  wcel 2145  {cab 2757  wrex 3062  c0 4063  ifcif 4225  cop 4322   Fn wfn 6026  cfv 6031  (class class class)co 6793  0cc0 10138  0cn0 11494  cz 11579  ..^cfzo 12673   mod cmo 12876  chash 13321   ++ cconcat 13489   substr csubstr 13491   cyclShift ccsh 13743
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1870  ax-4 1885  ax-5 1991  ax-6 2057  ax-7 2093  ax-9 2154  ax-10 2174  ax-11 2190  ax-12 2203  ax-13 2408  ax-ext 2751  ax-sep 4915  ax-nul 4923  ax-pr 5034
This theorem depends on definitions:  df-bi 197  df-an 383  df-or 837  df-3an 1073  df-tru 1634  df-ex 1853  df-nf 1858  df-sb 2050  df-eu 2622  df-mo 2623  df-clab 2758  df-cleq 2764  df-clel 2767  df-nfc 2902  df-ral 3066  df-rex 3067  df-rab 3070  df-v 3353  df-sbc 3588  df-dif 3726  df-un 3728  df-in 3730  df-ss 3737  df-nul 4064  df-if 4226  df-sn 4317  df-pr 4319  df-op 4323  df-uni 4575  df-br 4787  df-opab 4847  df-id 5157  df-xp 5255  df-rel 5256  df-cnv 5257  df-co 5258  df-dm 5259  df-iota 5994  df-fun 6033  df-fv 6039  df-ov 6796  df-oprab 6797  df-mpt2 6798  df-csh 13744
This theorem is referenced by:  cshword  13746  cshword2  41965
  Copyright terms: Public domain W3C validator