How to fix the procedure - wolfram-mathematica

Question

Help me, please!
There's the procedure operation[f_].
It works correctly and plot for functions:Cos,Sin. But, Unfortunately, it doesn't work for E^x and Log[E,x] and outputs errors, maybe because inputting not correct name of function or something else;(( What's the problem?
spxsin = {-1, -0.35, 0.3, 0.95, 1.6, 2.375, 3.15, 3.925, 4.7, 5.025,
5.35, 5.675, 6};
spxcos = {-1, -0.75, -0.5, -0.25, 0, 0.775, 1.55, 2.325, 3.1, 3.825,
4.55, 5.275, 6};
spxlny = {-1, 0.75, 2.5, 4.25, 6};
spxey = {-1, 0.75, 2.5, 4.25, 6};
operation[f_] := Block[{data},
data = Table[{x, f[x]}, {x, -1, 6, 0.1}];
Graphics[{Thick, Blue, Line[data],
Green, Table[Point[{spx[­[i]], f[spx[­[i]]]}], {i, 1, Length[spx]}],
Pink, Opacity[.7],
Table[Rectangle[{spx[­[i]], f[spx[­[i]]]}, {spx[­[i + 1]],
f[spx[­[i + 1]]]}], {i, 1, Length[spx] - 1}]
}, Axes -> True]]
Which[ f == Sin, spx := spxsin, f == Cos, spx := spxcos, f == E^x ,
spx := spxlny, f == Log, spx := spxey]
operation[Sin]
operation[Cos]
operation[E^x]
operation[Log]

Answer 1

Edit now tested: you can pass pure functions to your operation, so instead of: operation[E^x] try
operation[E^# &]
or for example if you wanted a base 2 log it would be
operation[Log[2,#]&]
A few other things to point out: Log fails simply because your x table range is negative.
Also, the Which statement you have doesn't do anything. Being outside your function, f is not defined so none of the conditionals are True. Moving Which inside the function, this works:
spxsin = {-1, -0.35, 0.3, 0.95, 1.6, 2.375, 3.15, 3.925, 4.7, 5.025,
5.35, 5.675, 6};
spxcos = {-1, -0.75, -0.5, -0.25, 0, 0.775, 1.55, 2.325, 3.1, 3.825,
4.55, 5.275, 6};
spxlny = {-1, 0.75, 2.5, 4.25, 6};
spxey = {-1, 0.75, 2.5, 4.25, 6};
operation[f_] :=
Block[{data}, data = Table[{x, f[x]}, {x, -1, 6, 0.1}];
Clear[spx];
Which[
TrueQ[f == Sin], spx := spxsin,
TrueQ[f == Cos], spx := spxcos ,
TrueQ[f == (E^# &)], spx := spxey ];
Graphics[{Thick, Blue, Line[data], Green,
Table[{PointSize[.1], Point[{spx[[i]], f[spx[[i]]]}]}, {i, 1, Length[spx]}],
Pink, Opacity[.7],
Table[Rectangle[{spx[[i]], f[spx[[i]]]}, {spx[[i + 1]],
f[spx[[i + 1]]]}], {i, 1, Length[spx] - 1}]}, Axes -> True,
AspectRatio -> 1/GoldenRatio]]
Note each which test is wrapped in TrueQ to ensure it is either True or False ( the test Sin==Cos is not false for all values and so does not return False )
operation[Sin]
operation[Cos]
operation[E^# &]
Now if you want Exp to also work you need to explicitly put that form in your Which statement. ( f==(E^#&) || f==Exp )

Answer 2

Euler's E needs to be entered as Esc ee Esc.
It looks to me at you entered is a standard E.
Note also that Exp is the exponential function in Mathematica.