midpoint {qpcR}

Calculation of the 'midpoint' region

Description

Calculates the exponential region midpoint using the algorithm described in Peirson et al. (2003).

Usage

midpoint(object, noise.cyc = 1:5)

Arguments

object

a fitted object of class 'pcrfit'.

noise.cyc

the cycles defining the background noise.

Details

The 'midpoint' region is calculated by

F_{noise} \cdot \sqrt{\frac{F_{max}}{F_{noise}}}

with F_{noise} = the standard deviation of the background cycles and F_{max} = the maximal fluorescence.

Value

A list with the following components:

f.mp

the 'midpoint' fluorescence.

cyc.mp

the 'midpoint' cycle, as predicted from f.mp.

Author(s)

Andrej-Nikolai Spiess

References

Experimental validation of novel and conventional approaches to quantitative real-time PCR data analysis.
Peirson SN, Butler JN & Foster RG.
Nucleic Acids Research (2003), 31: e73.

Examples

m1 <- pcrfit(reps, 1, 2, l5)
mp <- midpoint(m1) 
plot(m1)
abline(h = mp$f.mp, col = 2)
abline(v = mp$mp, col = 2)