# get.n: Calculate the number of grains required to achieve a desired... In provenance: Statistical Toolbox for Sedimentary Provenance Analysis

## Description

Returns the number of grains that need to be analysed to decrease the likelihood of missing any fraction greater than a given size below a given level.

## Usage

 `1` ```get.n(p = 0.05, f = 0.05) ```

## Arguments

 `p` the probability that all n grains in the sample have missed at least one fraction of size f `f` the size of the smallest resolvable fraction (0

## Value

the number of grains needed to reduce the chance of missing at least one fraction f of the total population to less than p

## References

Vermeesch, Pieter. "How many grains are needed for a provenance study?." Earth and Planetary Science Letters 224.3 (2004): 441-451.

## Examples

 ```1 2 3 4``` ```# number of grains required to be 99% that no fraction greater than 5% was missed: print(get.n(0.01)) # number of grains required to be 90% that no fraction greater than 10% was missed: print(get.n(p=0.1,f=0.1)) ```

provenance documentation built on Jan. 3, 2018, 9:33 a.m.