In this video I'm going to show you how to develop a histogram
using a set of wind data. So you can see
over here, the sample number which we won't necessarily be using
the hour, so this is a time record it's
a continuous numer. And the wind speed in meters per
second as well as miles per hour. We're not going to look at the
miles per hour. First I'm going to point out, if you go to the data
tab in excel and on the right hand side
if you don't see data analysis and solver
you may need to go and add these in. You go to file,
options, go to add-ins, and
manage excel add-ins, go, and you can select
these here. So the analysis tool pack as well as the solver add-in
are things that you might find useful for this class.
So next I'm going to define the range of
bins that I want to explore for my histogram.
So I've just developed a column which is just adding
1 to each progressive row down to 25
so these are meters per second. So I'm going to go to data
analysis now and select histogram
and the imput range is going
to be my meters per second column
the bin range is this column
that I just developed
and...
it's going to pop up in a new worksheet.
So it's created sheet 4 here. So now I've got
the frequency
that the wind blows within each bin. Now, what I really want is
to turn this into what will be similar to the Weibull distribution
is to normalize it by the number of observations. So I'm just
going to sum how many observations there are
in this column and there's 4, 464.
This was a month's worth of data, I should
mention. And then I'm just going to just take each of these and
divide them by the number of observations
to get a percentage of the time rather than a number of hours.
And actually this was not hourly data so it wasn't even
a number of hours. Okay, so now if I plot,
these 2 columns
should look something like a Weibull curve.
Something like a Weibull curve...
and similarly we can plot a
Weibull distribution on top of that. And actually I'm going to
change this from a
line chart to a bar chart.
