# M-step to maximize theta

### Description

This is a utility function for `maxEM`

### Usage

1 | ```
mstep(x, theta, phi)
``` |

### Arguments

`x` |
a zero-one indicator matrix whose rows correspond to unique lengths with rownames indicating those lengths |

`theta` |
a vector of the abundance estimates. |

`phi` |
a vector of the probabilities of sonicant lengths. |

### Details

The M-step for theta is computed. Probably, there is no need to use this function directly, but just in case it is here.

### Value

a vector like the input `theta`

### Author(s)

Charles C. Berry

### See Also

`maxEM`

### Examples

1 2 3 4 5 | ```
mat <- diag(10)
mat[ ,10 ] <- 1.0
phi1 <- prop.table( rep(1,10))
theta1 <- 1:10
sonicLength:::mstep( mat, theta1,phi1)
``` |