# Missing point while plotting [duplicate] I though I will get a point at f(2)=6, anyone please help me I am new on programming, Thanks

• Plot works by discretely sampling the function. This would only work in the unlikely event Plot happens to sample exactly at x=2. Best bet here is to just use Epilog->Point[{2,6}] – george2079 Oct 20 '17 at 22:00
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• Use the code here and do PlotPiecewise[Piecewise[{{2^x, x != 2}, {6, x == 2}}], {x, -1, 3}]. – march Oct 20 '17 at 22:55

There is nothing wrong with your piecewise function, but Mathematica's plotting algorithm really can't show an intervals are less than single pixel. A single real number, which has measure zero, simply doesn't show up. There are ways to deal with the problem. Here are two. One of them may be what you want.

### Force Plot to draw the point.

pw1[x_] := Piecewise[{{2^x, x != 2}}, 6]
Plot[pw1[ x], {x, -1, 3}, Epilog -> {Point[{2, pw1}]}] ### Redefine the function so it takes the value 6 over a large enough interval.

With[{d = .015},
With[{span = 2 + {-1, 1} d},
pw2[x_] := Piecewise[{{6, Between[x, span]}}, 2^x]]]
Plot[pw2[x], {x, -1, 3}, PlotPoints -> 80] Note that I had to ask for extra plot points to get the small interval to show up.