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# DAL ToolBox
# version 1.0.777

source("https://raw.githubusercontent.com/cefet-rj-dal/daltoolbox/main/jupyter.R")

#loading DAL
load_library("daltoolbox") 

#for ploting
load_library("ggplot2")
load_library("dplyr")

Loading required package: daltoolbox

Registered S3 method overwritten by 'quantmod':
  method            from
  as.zoo.data.frame zoo 


Attaching package: ‘daltoolbox’


The following object is masked from ‘package:base’:

    transform


Loading required package: ggplot2

Loading required package: dplyr


Attaching package: ‘dplyr’


The following objects are masked from ‘package:stats’:

    filter, lag


The following objects are masked from ‘package:base’:

    intersect, setdiff, setequal, union

Maximum curvature¶

If the curve is decreasing, use maximum curvature analysis. It brings a trade-off between having lower x values (with not so low y values) and having higher x values (not having to much decrease in y values).

In [2]:

x <- seq(from=1,to=10,by=0.5)
dat <- data.frame(x = x, value = -log(x), variable = as.factor("log"))
myfit <- fit_curvature_max()
res <- transform(myfit, dat$value)
head(res)

A data.frame: 1 × 3
	x	y	yfit
	<int>	<dbl>	<dbl>
1	9	-1.609438	9.224359e-08

In [3]:

grf <- plot_scatter(dat, label_x = "dimensions", label_y = "cumulative variance", colors="black") + 
    theme(text = element_text(size=16))
plot(grf + geom_vline(xintercept = dat$x[res$x], linetype="dashed", color = "red", size=0.5))

Warning message:
“Using `size` aesthetic for lines was deprecated in ggplot2 3.4.0.
ℹ Please use `linewidth` instead.”

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