Theorem cshword 13537

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 13307	. . . . 5 ⊢ (𝑊 ∈ Word 𝑉 ↔ ∃𝑙 ∈ ℕ0 𝑊:(0..^𝑙)⟶𝑉)
2		ffn 6045	. . . . . 6 ⊢ (𝑊:(0..^𝑙)⟶𝑉 → 𝑊 Fn (0..^𝑙))
3	2	reximi 3011	. . . . 5 ⊢ (∃𝑙 ∈ ℕ0 𝑊:(0..^𝑙)⟶𝑉 → ∃𝑙 ∈ ℕ0 𝑊 Fn (0..^𝑙))
4	1, 3	sylbi 207	. . . 4 ⊢ (𝑊 ∈ Word 𝑉 → ∃𝑙 ∈ ℕ0 𝑊 Fn (0..^𝑙))
5		fneq1 5979	. . . . . 6 ⊢ (𝑤 = 𝑊 → (𝑤 Fn (0..^𝑙) ↔ 𝑊 Fn (0..^𝑙)))
6	5	rexbidv 3052	. . . . 5 ⊢ (𝑤 = 𝑊 → (∃𝑙 ∈ ℕ0 𝑤 Fn (0..^𝑙) ↔ ∃𝑙 ∈ ℕ0 𝑊 Fn (0..^𝑙)))
7	6	elabg 3351	. . . 4 ⊢ (𝑊 ∈ Word 𝑉 → (𝑊 ∈ {𝑤 ∣ ∃𝑙 ∈ ℕ0 𝑤 Fn (0..^𝑙)} ↔ ∃𝑙 ∈ ℕ0 𝑊 Fn (0..^𝑙)))
8	4, 7	mpbird 247	. . 3 ⊢ (𝑊 ∈ Word 𝑉 → 𝑊 ∈ {𝑤 ∣ ∃𝑙 ∈ ℕ0 𝑤 Fn (0..^𝑙)})
9		cshfn 13536	. . 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 488	. 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 4092	. . . . 5 ⊢ (𝑊 = ∅ → if(𝑊 = ∅, ∅, ((𝑊 substr ⟨(𝑁 mod (#‘𝑊)), (#‘𝑊)⟩) ++ (𝑊 substr ⟨0, (𝑁 mod (#‘𝑊))⟩))) = ∅)
12	11	adantr 481	. . . 4 ⊢ ((𝑊 = ∅ ∧ (𝑊 ∈ Word 𝑉 ∧ 𝑁 ∈ ℤ)) → if(𝑊 = ∅, ∅, ((𝑊 substr ⟨(𝑁 mod (#‘𝑊)), (#‘𝑊)⟩) ++ (𝑊 substr ⟨0, (𝑁 mod (#‘𝑊))⟩))) = ∅)
13		oveq1 6657	. . . . . . . 8 ⊢ (𝑊 = ∅ → (𝑊 substr ⟨(𝑁 mod (#‘𝑊)), (#‘𝑊)⟩) = (∅ substr ⟨(𝑁 mod (#‘𝑊)), (#‘𝑊)⟩))
14		swrd0 13434	. . . . . . . 8 ⊢ (∅ substr ⟨(𝑁 mod (#‘𝑊)), (#‘𝑊)⟩) = ∅
15	13, 14	syl6eq 2672	. . . . . . 7 ⊢ (𝑊 = ∅ → (𝑊 substr ⟨(𝑁 mod (#‘𝑊)), (#‘𝑊)⟩) = ∅)
16		oveq1 6657	. . . . . . . 8 ⊢ (𝑊 = ∅ → (𝑊 substr ⟨0, (𝑁 mod (#‘𝑊))⟩) = (∅ substr ⟨0, (𝑁 mod (#‘𝑊))⟩))
17		swrd0 13434	. . . . . . . 8 ⊢ (∅ substr ⟨0, (𝑁 mod (#‘𝑊))⟩) = ∅
18	16, 17	syl6eq 2672	. . . . . . 7 ⊢ (𝑊 = ∅ → (𝑊 substr ⟨0, (𝑁 mod (#‘𝑊))⟩) = ∅)
19	15, 18	oveq12d 6668	. . . . . 6 ⊢ (𝑊 = ∅ → ((𝑊 substr ⟨(𝑁 mod (#‘𝑊)), (#‘𝑊)⟩) ++ (𝑊 substr ⟨0, (𝑁 mod (#‘𝑊))⟩)) = (∅ ++ ∅))
20	19	adantr 481	. . . . 5 ⊢ ((𝑊 = ∅ ∧ (𝑊 ∈ Word 𝑉 ∧ 𝑁 ∈ ℤ)) → ((𝑊 substr ⟨(𝑁 mod (#‘𝑊)), (#‘𝑊)⟩) ++ (𝑊 substr ⟨0, (𝑁 mod (#‘𝑊))⟩)) = (∅ ++ ∅))
21		wrd0 13330	. . . . . 6 ⊢ ∅ ∈ Word 𝑉
22		ccatrid 13370	. . . . . 6 ⊢ (∅ ∈ Word 𝑉 → (∅ ++ ∅) = ∅)
23	21, 22	ax-mp 5	. . . . 5 ⊢ (∅ ++ ∅) = ∅
24	20, 23	syl6req 2673	. . . 4 ⊢ ((𝑊 = ∅ ∧ (𝑊 ∈ Word 𝑉 ∧ 𝑁 ∈ ℤ)) → ∅ = ((𝑊 substr ⟨(𝑁 mod (#‘𝑊)), (#‘𝑊)⟩) ++ (𝑊 substr ⟨0, (𝑁 mod (#‘𝑊))⟩)))
25	12, 24	eqtrd 2656	. . 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 4095	. . . 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 481	. . 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 831	. 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 2656	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 384   = wceq 1483   ∈ wcel 1990  {cab 2608  ∃wrex 2913  ∅c0 3915  ifcif 4086  ⟨cop 4183   Fn wfn 5883  ⟶wf 5884  ‘cfv 5888  (class class class)co 6650  0cc0 9936  ℕ₀cn0 11292  ℤcz 11377  ..^cfzo 12465   mod cmo 12668  #chash 13117  Word cword 13291   ++ cconcat 13293   substr csubstr 13295   cyclShift ccsh 13534

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1722  ax-4 1737  ax-5 1839  ax-6 1888  ax-7 1935  ax-8 1992  ax-9 1999  ax-10 2019  ax-11 2034  ax-12 2047  ax-13 2246  ax-ext 2602  ax-rep 4771  ax-sep 4781  ax-nul 4789  ax-pow 4843  ax-pr 4906  ax-un 6949  ax-cnex 9992  ax-resscn 9993  ax-1cn 9994  ax-icn 9995  ax-addcl 9996  ax-addrcl 9997  ax-mulcl 9998  ax-mulrcl 9999  ax-mulcom 10000  ax-addass 10001  ax-mulass 10002  ax-distr 10003  ax-i2m1 10004  ax-1ne0 10005  ax-1rid 10006  ax-rnegex 10007  ax-rrecex 10008  ax-cnre 10009  ax-pre-lttri 10010  ax-pre-lttrn 10011  ax-pre-ltadd 10012  ax-pre-mulgt0 10013

This theorem depends on definitions:  df-bi 197  df-or 385  df-an 386  df-3or 1038  df-3an 1039  df-tru 1486  df-ex 1705  df-nf 1710  df-sb 1881  df-eu 2474  df-mo 2475  df-clab 2609  df-cleq 2615  df-clel 2618  df-nfc 2753  df-ne 2795  df-nel 2898  df-ral 2917  df-rex 2918  df-reu 2919  df-rab 2921  df-v 3202  df-sbc 3436  df-csb 3534  df-dif 3577  df-un 3579  df-in 3581  df-ss 3588  df-pss 3590  df-nul 3916  df-if 4087  df-pw 4160  df-sn 4178  df-pr 4180  df-tp 4182  df-op 4184  df-uni 4437  df-int 4476  df-iun 4522  df-br 4654  df-opab 4713  df-mpt 4730  df-tr 4753  df-id 5024  df-eprel 5029  df-po 5035  df-so 5036  df-fr 5073  df-we 5075  df-xp 5120  df-rel 5121  df-cnv 5122  df-co 5123  df-dm 5124  df-rn 5125  df-res 5126  df-ima 5127  df-pred 5680  df-ord 5726  df-on 5727  df-lim 5728  df-suc 5729  df-iota 5851  df-fun 5890  df-fn 5891  df-f 5892  df-f1 5893  df-fo 5894  df-f1o 5895  df-fv 5896  df-riota 6611  df-ov 6653  df-oprab 6654  df-mpt2 6655  df-om 7066  df-1st 7168  df-2nd 7169  df-wrecs 7407  df-recs 7468  df-rdg 7506  df-1o 7560  df-oadd 7564  df-er 7742  df-en 7956  df-dom 7957  df-sdom 7958  df-fin 7959  df-card 8765  df-pnf 10076  df-mnf 10077  df-xr 10078  df-ltxr 10079  df-le 10080  df-sub 10268  df-neg 10269  df-nn 11021  df-n0 11293  df-z 11378  df-uz 11688  df-fz 12327  df-fzo 12466  df-hash 13118  df-word 13299  df-concat 13301  df-substr 13303  df-csh 13535

This theorem is referenced by:  cshw0  13540  cshwmodn  13541  cshwcl  13544  cshwlen  13545  cshwidxmod  13549  repswcshw  13558