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

 get.n R Documentation

## Calculate the number of grains required to achieve a desired level of sampling resolution

### 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

``````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

``````# 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 Aug. 28, 2023, 5:07 p.m.