Frequency histogram for selected values in a vector

I have 3 vectors time, wind speed and wind direction. I want to plot a histogram showing the relative frequency (or the absolute frequency) of occurrence of wind speeds below 4 knots for every 30 degree arc. In that way i will be able to see which 30 degree arc has the highest frequency of wind speeds below 4 knots.

[Rik]

And your question is?

Have a read here and here. It will greatly improve your chances of getting an answer.

[Dimitrios Bentis]

I do not know how to plot a histogram with the relative frequencies of wind speeds below 4 knots. How can i do that?

Answer 1

[Rik]

You can use logical indexing to filter your data:

LowWindData=data(WindSpeed<4);
histogram(LowWindData)

See doc histogram what other options you have to achieve a result that best suits your needs.

[Dimitrios Bentis]

Than you very much for your help.

I was searching for something like this: LowWindData=WindDirection(WindSpeed<4) histogram(LowWindData)

I understand now.

[Dimitrios Bentis]

I still can't find how to get the relative frequency of that histogram. It plots the absolute frequency. How do i get the same histogram but with relative instead of absolute frequency?

[Rik]

Why don't you read the documentation?

'Normalization' — Type of normalization
'count' (default) | 'probability' | 'countdensity' | 'pdf' | 'cumcount' | 'cdf'