File:PiecewiseMonoDiff.pdf

Summary

Description
English: The function is an example of a piecewise monotonic and piecewise differentiable function. The intervals the domain is partioned in differ by property, they are and for monotonicity, and , , and for differentiability,

The function definition doesn't involve an explicit case distinction. While the usual definition uses a case distinction, so does addition on natural numbers which is employed, directly or indirectly, by all arithmetic operations on , , , , and . Hence, indirect use of case distinctions cannot be avoided in any function definition whatsoever.

The function (not depicted) is piecewise monotonic but built from arithmetic operations only.
Date
Source Own work
Author Jochen Burghardt
Other versions File:PiecewiseMonoDiff.pdf * File:PiecewiseMonoDiff_svg.svg
Gnuplot source code
set title "min ( 1, x^2 ) is piecewise monotonic and piecewise differentiable"
set grid
#set key left bottom
set xrange [-4:+4]
set yrange [-0.25:+1.10]
set samples 1000

f(x) = ( x*x < 1 ? x*x : 1 )
plot f(x) with lines lw 2 lt 7 title ""
set label "min ( 1, x^2 )" at -3.70 , 0.95 tc lt 7

# mono
set arrow from  0.00 , -0.10 to  0.00 , -0.06 nohead lc 1 lw 2
set arrow from -0.05 , -0.08 to -4.00 , -0.08        lc 1 lw 1
set arrow from +0.05 , -0.08 to +4.00 , -0.08        lc 1 lw 1
set label "monotonicity intervals"      at -3.70 , -0.05 tc lt 1

# diff
set arrow from -1.00 , -0.20 to -1.00 , -0.16 nohead lc 2 lw 2
set arrow from +1.00 , -0.20 to +1.00 , -0.16 nohead lc 2 lw 2
set arrow from -1.05,  -0.18 to -4.00 , -0.18        lc 2 lw 1
set arrow from -0.95,  -0.18 to +0.95 , -0.18 nohead lc 2 lw 1
set arrow from +1.05,  -0.18 to +4.00 , -0.18        lc 2 lw 1
set label "differentiability intervals" at -3.70 , -0.15 tc lt 2

pause -1

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Category:CC-Zero#PiecewiseMonoDiff.pdf
Category:Self-published work Category:Monotonicity Category:Differentiability (functions) Category:Images with Gnuplot source code Category:Files by User:Jochen Burghardt
Category:CC-Zero Category:Differentiability (functions) Category:Files by User:Jochen Burghardt Category:Images with Gnuplot source code Category:Monotonicity Category:Self-published work