How to plot a histogram given a set of frequencies for data values?

Question

I have generated many random variables within a specific function, and have counted them up. So far, I have counted the variables:

 bcount1=BinCounts[function,{0,20,1}]
 {86,10,2,2,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0}

Now I need to generate a histogram with a bin width of 1 that'll display something like:

x-axis 0 to 1 ---> a bar 86 units high x-axis 1 to 2 ---> a bar 10 units high x-axis 2 to 3 --> a bar 2 units high

and so on and so forth....however the Histogram function is giving me the reverse. It's telling me something from 80 to 100 is a bar 1 unit high..

Can I get some help with appropriate syntax?

Answer 1

bincounts = {86, 10, 2, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
bins = Range[0, 20, 1];

You can use BarChart:

BarChart[bincounts]

Or Histogram after reconstructing an input data set using bins and bincounts:

Histogram[Flatten[ConstantArray[##] & @@@ Transpose[{Most@bins, bincounts}]]]

Answer 2

data = {86, 10, 2, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
BarChart[data, ChartLabels -> Range[20]] 

If you must have a true histogram:

Histogram[Flatten[Table[i, {i, Length[data]}, {j, data[[i]]}]]]

Answer 3

values = Range[0, 20];
frequencies = {86, 10, 2, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
n = Length[values]; (* 21 *)
data = Flatten@Array[Table[values[[#]], {frequencies[[#]]}] &, n];

Histogram[data, {First@values, Last@values, 1}]