std: Sieve Test Data Object

In sievetest: Laboratory Sieve Test Reporting Functions

Description

Functions to create, test and subset a std object.

Usage

std(a, r, desc = desc.std(), lmargs = list())
is.std(x)
## S3 method for class 'std'
x[i, ...]

Arguments

a	A vector of sieve net aperture sizes in micrometers, zero size means the receiver.
i	An integer or vector of integers
r	Mass percent of remaining material on the sieve, vector with the same length as vector a, sum should be equal 100, if not the function will give warning and recalculate the values. If the value is 0, then will be excluded with warning.
desc	A description meta data prepared by desc.std
lmargs	A list of additional arguments to lm
x	An object of std class
...	Not used

Details

Basically the std object is list of lists, in the first level (trunk) are stored particular sieve test samples, in the second level (branches) are stored details of each single sample. If there is only one sample in the std object, then the length will be 1. The object can be created by hand using std function or by reading the basic information from CSV file using read.std function. Once the std object exists, it can be sub-selected using x[i] or concatenated by c(...).

Value

Both std(a,r) and x[i] functions return std object, x[[i]] returns list holding following informations:

Description	Terse description of a sample
Title	Title of particular measurement
Sample	Name of the sample
Unit	To which unit the sample belongs
Date	Day when the sample was taken
stdata	Data frame with given and calculated values
lmfit	Result of linear model fit, lm object
RRcoefficients	List of coefficients for Rosin - Rammler distribution
size	List of characteristic sizes of Rosin - Rammler distribution

The is.std(x) function returns logical value.

See Also

read.std, c.std, summary.std, tweak.std

Examples

## create std
sieve_aperture_size <- c(500, 200, 90, 0)
mass_ppc_retained <- c(1.01, 24, 42.8, 32.190)
# some meta data:
md <- desc.std("Coal powder, learning std")
# sieve test data (std) object
my_sample <- std(a=sieve_aperture_size, r=mass_ppc_retained, desc=md)
is.std(my_sample)

Example output

Warning message:
In std(a = sieve_aperture_size, r = mass_ppc_retained, desc = md) :
  Insufficient metadata.
[1] TRUE

sievetest documentation built on May 2, 2019, 8:13 a.m.