# Finds the Inflection Point of a Curve

Implementation of methods Extremum Surface Estimator (ESE) and Extremum Distance Estimator (EDE) to identify the inflection point of a curve . Christopoulos, DT (2014) . Christopoulos, DT (2016) < https://veltech.edu.in/wp-content/uploads/2016/04/Paper-04-2016.pdf> . Christopoulos, DT (2016) .

• Because it does not imply any kind of functional hypothesis for the data under examination
• Because it can give you an estimation despite the level of noise added to initial data
• Because it is fast and can use parallel computing if you ask for it
• Due to its simplicity it can handle data sets with more than a million rows in negligible execution time
• It uses sophisticated iterative methods like bisection of Numerical Analysis and locates the inflection point when it is not directly visible form the first sight

# Use of parallel computing under request (doparallel=TRUE) for the functions:

ese()

bese()

findiplist()

findipiterplot()

## Repair of function findipiterplot()

1. Fix bugs in calling the function
2. Remove indirect methods CRESE, CREDE due to their limited functionality
3. Plot in two separate pdfs 'ese_iterations.pdf' and 'ede_iterations.pdf'
4. Check for the existence of sufficient number of results before creating confidence intervals

### What's new in version 1.2

1. The function eixf(x, y, f, i) was removed as not essentially necessary
2. New functions with self declaring names were added: *ese(x,y,index) *bese(x,y,index) *ede(x,y,index) *edeci(x,y,index) *bede(x,y,index) All functions require length(x)>=4 in order to create numeric output
3. Thef unction findipiterplot(x,y,index) was improved and became findipiterplot(x, y, index, plots = TRUE, crossrun = FALSE, ci = FALSE)
4. Changes in NAMESPACE, added folder inst/CITATION
5. Reference to new paper:

Demetris T. Christopoulos, On the efficient identification of an inflection point, International Journal of Mathematics and Scientific Computing, (ISSN: 2231-5330), vol. 6(1), 2016

# Reference manual

install.packages("inflection")

1.3.5 by Demetris T. Christopoulos, 2 years ago

https://CRAN.R-project.org/package=inflection

Browse source code at https://github.com/cran/inflection

Authors: Demetris T. Christopoulos

Documentation:   PDF Manual

GPL (>= 2) license

Imports parallel, stats, graphics, grDevices

Suggests knitr, rmarkdown

Depended on by RootsExtremaInflections.

Suggested by RRphylo.

See at CRAN