R: Bivariate (Two-Dimensional) Frequency Distribution

Freq2D {DescTools} | R Documentation

## Bivariate (Two-Dimensional) Frequency Distribution

### Description

Calculate a frequency distribution for two continuous variables.

### Usage

    Freq2D(x, ...)

    ## S3 method for class 'formula'
    Freq2D(formula, data, subset, ...)

    ## Default S3 method:
    Freq2D(x, y, n=20, pad=0, dnn=NULL, ...)

### Arguments

`x` | a vector of x values, or a data frame whose first two columns contain the x and y values.
`y` | a vector of y values.
`formula` | a `formula`, such as `y~x`.
`data` | a `data.frame`, `matrix`, or `list` from which the variables in `formula` should be taken.
`subset` | an optional vector specifying a subset of observations to be used.
`n` | the desired number of bins for the output, a scalar or a vector of length 2.
`pad` | number of rows and columns to add to each margin, containing only zeros.
`dnn` | the names to be given to the dimensions in the result.
`...` | named arguments to be passed to the default method.

### Details

The exact number of bins is determined by the `pretty` function, based on the value of `n`.

Padding the margins with zeros can be helpful for subsequent analysis, such as smoothing.

The `print` logical flag only has an effect when `layout=1`.

### Value

The `layout` argument specifies one of the following formats for the binned frequency output:

1. `matrix` that is easy to read, aligned like a scatterplot.

2. `list` with three elements (x, y, matrix) that can be passed to various plotting functions.

3. `data.frame` with three columns (x, y, frequency) that can be analyzed further.

### Author(s)

Arni Magnusson <arnima@hafro.is>

### See Also

`cut`, `table`, and `print.table` are the basic underlying functions.

### Examples

    Freq2D(quakes$long, quakes$lat, dnn="")
    Freq2D(lat~long, quakes, n=c(10,20), pad=1)

    # range(Freq2D(saithe, print=FALSE))

    # Layout, plot
    # Freq2D(saithe, layout=2)
    # Freq2D(saithe, layout=3)
    # contour(Freq2D(saithe, layout=2))
    # lattice::contourplot(Freq~Bio+HR, Freq2D(saithe,layout=3))

[Package DescTools version 0.99.28 Index]