Revisions to ReplaceList doesn't apply rules down to subparts

added 266 characters in body

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edited Dec 13, 2019 at 23:21

31.3k
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Try this instead

expr := Hold[Cos[\[Omega]Hold[Cos[ω t - \[Pi]π/4 + 3 \[Pi]π/4]]
rule := Cos[a_ + b_] :> X[a, b]
ReleaseHold[ReplaceAll[expr, {rule}]]

X[t [Omega], [Pi]/2]
X[t ω, π/2]

In reply to the comment

expr := Hold[Cos[\[Omega]Hold[Cos[ω t - \[Pi]π/4 + 3 \[Pi]π/4]]
rule := Cos[a_] :> (a /. List -> X)
ReleaseHold[ReplaceAll[expr /. Plus -> List, {rule}]]

X[t [Omega], -([Pi]/4), (3 [Pi])/4]
X[t ω, -(π/4), (3 π)/4]

I'm sure there is a simpler way.

Try this instead

expr := Hold[Cos[\[Omega] t - \[Pi]/4 + 3 \[Pi]/4]]
rule := Cos[a_ + b_] :> X[a, b]
ReleaseHold[ReplaceAll[expr, {rule}]]

X[t [Omega], [Pi]/2]

In reply to the comment

expr := Hold[Cos[\[Omega] t - \[Pi]/4 + 3 \[Pi]/4]]
rule := Cos[a_] :> (a /. List -> X)
ReleaseHold[ReplaceAll[expr /. Plus -> List, {rule}]]

X[t [Omega], -([Pi]/4), (3 [Pi])/4]

I'm sure there is a simpler way.

Try this instead

expr := Hold[Cos[ω t - π/4 + 3 π/4]]
rule := Cos[a_ + b_] :> X[a, b]
ReleaseHold[ReplaceAll[expr, {rule}]]

X[t ω, π/2]

In reply to the comment

expr := Hold[Cos[ω t - π/4 + 3 π/4]]
rule := Cos[a_] :> (a /. List -> X)
ReleaseHold[ReplaceAll[expr /. Plus -> List, {rule}]]

X[t ω, -(π/4), (3 π)/4]

I'm sure there is a simpler way.

added 266 characters in body

Source Link

edited Dec 13, 2019 at 23:18

Chris Degnen

31.3k
2
56
109

Try this instead

expr := Hold[Cos[\[Omega] t - \[Pi]/4 + 3 \[Pi]/4]]
rule := Cos[a_ + b_] :> X[a, b]
ReleaseHold[ReplaceAll[expr, {rule}]]

X[t [Omega], [Pi]/2]

In reply to the comment

expr := Hold[Cos[\[Omega] t - \[Pi]/4 + 3 \[Pi]/4]]
rule := Cos[a_] :> (a /. List -> X)
ReleaseHold[ReplaceAll[expr /. Plus -> List, {rule}]]

X[t [Omega], -([Pi]/4), (3 [Pi])/4]

I'm sure there is a simpler way.

Try this instead

expr := Hold[Cos[\[Omega] t - \[Pi]/4 + 3 \[Pi]/4]]
rule := Cos[a_ + b_] :> X[a, b]
ReleaseHold[ReplaceAll[expr, {rule}]]

X[t [Omega], [Pi]/2]

Try this instead

expr := Hold[Cos[\[Omega] t - \[Pi]/4 + 3 \[Pi]/4]]
rule := Cos[a_ + b_] :> X[a, b]
ReleaseHold[ReplaceAll[expr, {rule}]]

X[t [Omega], [Pi]/2]

In reply to the comment

expr := Hold[Cos[\[Omega] t - \[Pi]/4 + 3 \[Pi]/4]]
rule := Cos[a_] :> (a /. List -> X)
ReleaseHold[ReplaceAll[expr /. Plus -> List, {rule}]]

X[t [Omega], -([Pi]/4), (3 [Pi])/4]

I'm sure there is a simpler way.

Source Link

created Dec 13, 2019 at 22:46

Chris Degnen

31.3k
2
56
109

Try this instead

expr := Hold[Cos[\[Omega] t - \[Pi]/4 + 3 \[Pi]/4]]
rule := Cos[a_ + b_] :> X[a, b]
ReleaseHold[ReplaceAll[expr, {rule}]]

X[t [Omega], [Pi]/2]

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