# matrixSmooth: Smooth a Matrix In oce: Analysis of Oceanographic Data

## Description

The values on the edge of the matrix are unaltered. For interior points, the result is defined in terms in terms of the original as follows. r_[i,j] = (2 m_[i,j] + m_[i-1,j] + m_[i+1,j] + m_[i,j-1] + m_[i,j+1])/6. Note that missing values propagate to neighbours.

## Usage

 `1` ```matrixSmooth(m, passes = 1) ```

## Arguments

 `m` a matrix to be smoothed. `passes` an integer specifying the number of times the smoothing is to be applied.

## Value

A smoothed matrix.

Dan Kelley

## Examples

 ``` 1 2 3 4 5 6 7 8 9 10 11 12 13``` ```library(oce) opar <- par(no.readonly = TRUE) m <- matrix(rep(seq(0, 1, length.out=5), 5), nrow=5, byrow=TRUE) m[3, 3] <- 2 m1 <- matrixSmooth(m) m2 <- matrixSmooth(m1) m3 <- matrixSmooth(m2) par(mfrow=c(2, 2)) image(m, col=rainbow(100), zlim=c(0, 4), main="original image") image(m1, col=rainbow(100), zlim=c(0, 4), main="smoothed 1 time") image(m2, col=rainbow(100), zlim=c(0, 4), main="smoothed 2 times") image(m3, col=rainbow(100), zlim=c(0, 4), main="smoothed 3 times") par(opar) ```

### Example output ```Loading required package: testthat
Loading required package: gsw
pass=1
pass=1
pass=1
```

oce documentation built on March 28, 2021, 9:09 a.m.