Theorem cshword 13388

Description: Perform a cyclical shift for a word. (Contributed by Alexander van der Vekens, 20-May-2018.) (Revised by AV, 17-Nov-2018.)

Assertion

Ref	Expression
cshword	⊢ ((𝑊 ∈ Word 𝑉 ∧ 𝑁 ∈ ℤ) → (𝑊 cyclShift 𝑁) = ((𝑊 substr ⟨(𝑁 mod (#‘𝑊)), (#‘𝑊)⟩) ++ (𝑊 substr ⟨0, (𝑁 mod (#‘𝑊))⟩)))

Proof of Theorem cshword

Dummy variables 𝑙 𝑤 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		iswrd 13162	. . . . 5 ⊢ (𝑊 ∈ Word 𝑉 ↔ ∃𝑙 ∈ ℕ0 𝑊:(0..^𝑙)⟶𝑉)
2		ffn 5958	. . . . . 6 ⊢ (𝑊:(0..^𝑙)⟶𝑉 → 𝑊 Fn (0..^𝑙))
3	2	reximi 2994	. . . . 5 ⊢ (∃𝑙 ∈ ℕ0 𝑊:(0..^𝑙)⟶𝑉 → ∃𝑙 ∈ ℕ0 𝑊 Fn (0..^𝑙))
4	1, 3	sylbi 206	. . . 4 ⊢ (𝑊 ∈ Word 𝑉 → ∃𝑙 ∈ ℕ0 𝑊 Fn (0..^𝑙))
5		fneq1 5893	. . . . . 6 ⊢ (𝑤 = 𝑊 → (𝑤 Fn (0..^𝑙) ↔ 𝑊 Fn (0..^𝑙)))
6	5	rexbidv 3034	. . . . 5 ⊢ (𝑤 = 𝑊 → (∃𝑙 ∈ ℕ0 𝑤 Fn (0..^𝑙) ↔ ∃𝑙 ∈ ℕ0 𝑊 Fn (0..^𝑙)))
7	6	elabg 3320	. . . 4 ⊢ (𝑊 ∈ Word 𝑉 → (𝑊 ∈ {𝑤 ∣ ∃𝑙 ∈ ℕ0 𝑤 Fn (0..^𝑙)} ↔ ∃𝑙 ∈ ℕ0 𝑊 Fn (0..^𝑙)))
8	4, 7	mpbird 246	. . 3 ⊢ (𝑊 ∈ Word 𝑉 → 𝑊 ∈ {𝑤 ∣ ∃𝑙 ∈ ℕ0 𝑤 Fn (0..^𝑙)})
9		cshfn 13387	. . 3 ⊢ ((𝑊 ∈ {𝑤 ∣ ∃𝑙 ∈ ℕ0 𝑤 Fn (0..^𝑙)} ∧ 𝑁 ∈ ℤ) → (𝑊 cyclShift 𝑁) = if(𝑊 = ∅, ∅, ((𝑊 substr ⟨(𝑁 mod (#‘𝑊)), (#‘𝑊)⟩) ++ (𝑊 substr ⟨0, (𝑁 mod (#‘𝑊))⟩))))
10	8, 9	sylan 487	. 2 ⊢ ((𝑊 ∈ Word 𝑉 ∧ 𝑁 ∈ ℤ) → (𝑊 cyclShift 𝑁) = if(𝑊 = ∅, ∅, ((𝑊 substr ⟨(𝑁 mod (#‘𝑊)), (#‘𝑊)⟩) ++ (𝑊 substr ⟨0, (𝑁 mod (#‘𝑊))⟩))))
11		iftrue 4042	. . . . 5 ⊢ (𝑊 = ∅ → if(𝑊 = ∅, ∅, ((𝑊 substr ⟨(𝑁 mod (#‘𝑊)), (#‘𝑊)⟩) ++ (𝑊 substr ⟨0, (𝑁 mod (#‘𝑊))⟩))) = ∅)
12	11	adantr 480	. . . 4 ⊢ ((𝑊 = ∅ ∧ (𝑊 ∈ Word 𝑉 ∧ 𝑁 ∈ ℤ)) → if(𝑊 = ∅, ∅, ((𝑊 substr ⟨(𝑁 mod (#‘𝑊)), (#‘𝑊)⟩) ++ (𝑊 substr ⟨0, (𝑁 mod (#‘𝑊))⟩))) = ∅)
13		oveq1 6556	. . . . . . . 8 ⊢ (𝑊 = ∅ → (𝑊 substr ⟨(𝑁 mod (#‘𝑊)), (#‘𝑊)⟩) = (∅ substr ⟨(𝑁 mod (#‘𝑊)), (#‘𝑊)⟩))
14		swrd0 13286	. . . . . . . 8 ⊢ (∅ substr ⟨(𝑁 mod (#‘𝑊)), (#‘𝑊)⟩) = ∅
15	13, 14	syl6eq 2660	. . . . . . 7 ⊢ (𝑊 = ∅ → (𝑊 substr ⟨(𝑁 mod (#‘𝑊)), (#‘𝑊)⟩) = ∅)
16		oveq1 6556	. . . . . . . 8 ⊢ (𝑊 = ∅ → (𝑊 substr ⟨0, (𝑁 mod (#‘𝑊))⟩) = (∅ substr ⟨0, (𝑁 mod (#‘𝑊))⟩))
17		swrd0 13286	. . . . . . . 8 ⊢ (∅ substr ⟨0, (𝑁 mod (#‘𝑊))⟩) = ∅
18	16, 17	syl6eq 2660	. . . . . . 7 ⊢ (𝑊 = ∅ → (𝑊 substr ⟨0, (𝑁 mod (#‘𝑊))⟩) = ∅)
19	15, 18	oveq12d 6567	. . . . . 6 ⊢ (𝑊 = ∅ → ((𝑊 substr ⟨(𝑁 mod (#‘𝑊)), (#‘𝑊)⟩) ++ (𝑊 substr ⟨0, (𝑁 mod (#‘𝑊))⟩)) = (∅ ++ ∅))
20	19	adantr 480	. . . . 5 ⊢ ((𝑊 = ∅ ∧ (𝑊 ∈ Word 𝑉 ∧ 𝑁 ∈ ℤ)) → ((𝑊 substr ⟨(𝑁 mod (#‘𝑊)), (#‘𝑊)⟩) ++ (𝑊 substr ⟨0, (𝑁 mod (#‘𝑊))⟩)) = (∅ ++ ∅))
21		wrd0 13185	. . . . . 6 ⊢ ∅ ∈ Word 𝑉
22		ccatrid 13223	. . . . . 6 ⊢ (∅ ∈ Word 𝑉 → (∅ ++ ∅) = ∅)
23	21, 22	ax-mp 5	. . . . 5 ⊢ (∅ ++ ∅) = ∅
24	20, 23	syl6req 2661	. . . 4 ⊢ ((𝑊 = ∅ ∧ (𝑊 ∈ Word 𝑉 ∧ 𝑁 ∈ ℤ)) → ∅ = ((𝑊 substr ⟨(𝑁 mod (#‘𝑊)), (#‘𝑊)⟩) ++ (𝑊 substr ⟨0, (𝑁 mod (#‘𝑊))⟩)))
25	12, 24	eqtrd 2644	. . 3 ⊢ ((𝑊 = ∅ ∧ (𝑊 ∈ Word 𝑉 ∧ 𝑁 ∈ ℤ)) → if(𝑊 = ∅, ∅, ((𝑊 substr ⟨(𝑁 mod (#‘𝑊)), (#‘𝑊)⟩) ++ (𝑊 substr ⟨0, (𝑁 mod (#‘𝑊))⟩))) = ((𝑊 substr ⟨(𝑁 mod (#‘𝑊)), (#‘𝑊)⟩) ++ (𝑊 substr ⟨0, (𝑁 mod (#‘𝑊))⟩)))
26		iffalse 4045	. . . 4 ⊢ (¬ 𝑊 = ∅ → if(𝑊 = ∅, ∅, ((𝑊 substr ⟨(𝑁 mod (#‘𝑊)), (#‘𝑊)⟩) ++ (𝑊 substr ⟨0, (𝑁 mod (#‘𝑊))⟩))) = ((𝑊 substr ⟨(𝑁 mod (#‘𝑊)), (#‘𝑊)⟩) ++ (𝑊 substr ⟨0, (𝑁 mod (#‘𝑊))⟩)))
27	26	adantr 480	. . 3 ⊢ ((¬ 𝑊 = ∅ ∧ (𝑊 ∈ Word 𝑉 ∧ 𝑁 ∈ ℤ)) → if(𝑊 = ∅, ∅, ((𝑊 substr ⟨(𝑁 mod (#‘𝑊)), (#‘𝑊)⟩) ++ (𝑊 substr ⟨0, (𝑁 mod (#‘𝑊))⟩))) = ((𝑊 substr ⟨(𝑁 mod (#‘𝑊)), (#‘𝑊)⟩) ++ (𝑊 substr ⟨0, (𝑁 mod (#‘𝑊))⟩)))
28	25, 27	pm2.61ian 827	. 2 ⊢ ((𝑊 ∈ Word 𝑉 ∧ 𝑁 ∈ ℤ) → if(𝑊 = ∅, ∅, ((𝑊 substr ⟨(𝑁 mod (#‘𝑊)), (#‘𝑊)⟩) ++ (𝑊 substr ⟨0, (𝑁 mod (#‘𝑊))⟩))) = ((𝑊 substr ⟨(𝑁 mod (#‘𝑊)), (#‘𝑊)⟩) ++ (𝑊 substr ⟨0, (𝑁 mod (#‘𝑊))⟩)))
29	10, 28	eqtrd 2644	1 ⊢ ((𝑊 ∈ Word 𝑉 ∧ 𝑁 ∈ ℤ) → (𝑊 cyclShift 𝑁) = ((𝑊 substr ⟨(𝑁 mod (#‘𝑊)), (#‘𝑊)⟩) ++ (𝑊 substr ⟨0, (𝑁 mod (#‘𝑊))⟩)))

Syntax hints:  ¬ wn 3   → wi 4   ∧ wa 383   = wceq 1475   ∈ wcel 1977  {cab 2596  ∃wrex 2897  ∅c0 3874  ifcif 4036  ⟨cop 4131   Fn wfn 5799  ⟶wf 5800  ‘cfv 5804  (class class class)co 6549  0cc0 9815  ℕ₀cn0 11169  ℤcz 11254  ..^cfzo 12334   mod cmo 12530  #chash 12979  Word cword 13146   ++ cconcat 13148   substr csubstr 13150   cyclShift ccsh 13385

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1713  ax-4 1728  ax-5 1827  ax-6 1875  ax-7 1922  ax-8 1979  ax-9 1986  ax-10 2006  ax-11 2021  ax-12 2034  ax-13 2234  ax-ext 2590  ax-rep 4699  ax-sep 4709  ax-nul 4717  ax-pow 4769  ax-pr 4833  ax-un 6847  ax-cnex 9871  ax-resscn 9872  ax-1cn 9873  ax-icn 9874  ax-addcl 9875  ax-addrcl 9876  ax-mulcl 9877  ax-mulrcl 9878  ax-mulcom 9879  ax-addass 9880  ax-mulass 9881  ax-distr 9882  ax-i2m1 9883  ax-1ne0 9884  ax-1rid 9885  ax-rnegex 9886  ax-rrecex 9887  ax-cnre 9888  ax-pre-lttri 9889  ax-pre-lttrn 9890  ax-pre-ltadd 9891  ax-pre-mulgt0 9892

This theorem depends on definitions:  df-bi 196  df-or 384  df-an 385  df-3or 1032  df-3an 1033  df-tru 1478  df-ex 1696  df-nf 1701  df-sb 1868  df-eu 2462  df-mo 2463  df-clab 2597  df-cleq 2603  df-clel 2606  df-nfc 2740  df-ne 2782  df-nel 2783  df-ral 2901  df-rex 2902  df-reu 2903  df-rab 2905  df-v 3175  df-sbc 3403  df-csb 3500  df-dif 3543  df-un 3545  df-in 3547  df-ss 3554  df-pss 3556  df-nul 3875  df-if 4037  df-pw 4110  df-sn 4126  df-pr 4128  df-tp 4130  df-op 4132  df-uni 4373  df-int 4411  df-iun 4457  df-br 4584  df-opab 4644  df-mpt 4645  df-tr 4681  df-eprel 4949  df-id 4953  df-po 4959  df-so 4960  df-fr 4997  df-we 4999  df-xp 5044  df-rel 5045  df-cnv 5046  df-co 5047  df-dm 5048  df-rn 5049  df-res 5050  df-ima 5051  df-pred 5597  df-ord 5643  df-on 5644  df-lim 5645  df-suc 5646  df-iota 5768  df-fun 5806  df-fn 5807  df-f 5808  df-f1 5809  df-fo 5810  df-f1o 5811  df-fv 5812  df-riota 6511  df-ov 6552  df-oprab 6553  df-mpt2 6554  df-om 6958  df-1st 7059  df-2nd 7060  df-wrecs 7294  df-recs 7355  df-rdg 7393  df-1o 7447  df-oadd 7451  df-er 7629  df-en 7842  df-dom 7843  df-sdom 7844  df-fin 7845  df-card 8648  df-pnf 9955  df-mnf 9956  df-xr 9957  df-ltxr 9958  df-le 9959  df-sub 10147  df-neg 10148  df-nn 10898  df-n0 11170  df-z 11255  df-uz 11564  df-fz 12198  df-fzo 12335  df-hash 12980  df-word 13154  df-concat 13156  df-substr 13158  df-csh 13386

This theorem is referenced by:  cshw0  13391  cshwmodn  13392  cshwcl  13395  cshwlen  13396  cshwidxmod  13400  repswcshw  13409