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Why does my function CountChange not work the same way, Wellin says it does on page 117 of his book Essential of Programming...? CountChange is CountChange[coins_Llist] := Total[coins /. {p -> .01, n -> .05, d -> .10, q -> .25}] ...
I suspect there may be a mistake when Guillermo puts in his code D[u[t,x],t]==0/.t\[RightArrow]0 since the equation above is \[PartialD]u(0,x)/ \[PartialD]t==0 and not \[PartialD]u(t,x)/ \[PartialD]t==0. Please let me know if you agree or...
On page 117, in Mathematica Beyond Mathematics it states "You can also include a drop - down button.This will automatically be added when a parameter \ contains five or more choices as shown in the next example.In this \ case we have the...
Please show how to modify what follows so that it is correct. Clear[x1, x2] {{x1[t_], x2[t_]}} = {x1[t], x2[t]} /. DSolve [ {x1'[t] == 1 - 2.5 x1[t] + x2[t], x2'[t] == 2 x1[t] - x2[t], x1[0] == 0, ...
In the check your understanding section there is an option: StringReplace["lead",_"gold"] with the following explanation: "This replaces each letter separately, resulting in goldgoldgoldgold, instead of making just one replacement...