is.decreasing.on.x {FuzzyNumbers.Ext.2} | R Documentation |
Diagnosis a decreasing two-variable function toward x
Description
is.decreasing.on.x
tests for any fixed from
y.bound
, if the introduced two-variable function is decreasing toward
on the considered
x.bound
or not.
In other words, is.decreasing.on.x
returns TRUE
if the introduced function is decreasing function of
on the considered
x.bound
(for any fixed in
y.bound
); and it returns FALSE
otherwise.
The goal of introducing function is.increasing.on.x
in package FuzzyNumbers.Ext.2
is using in function f2apply
.
Usage
is.decreasing.on.x(fun, x.bound = c(-1, 1), y.bound = c(-1, 1), step = 0.01)
Arguments
fun |
a two-variable R function |
x.bound |
a vector with two real ordered elements which determine a bound on x-axis for checking the monotonic |
y.bound |
a vector with two real ordered elements which determine a bound on y-axis for checking the monotonic |
step |
a positive real-valued number which determine the increment of the considered sequence for checking the monotonic of the considered function. The default of |
Value
TRUE
for two-variable function f(x,y) which is decreasing toward x on x.bound
(for any fixed from
y.bound
); and otherwise FALSE
See Also
is.decreasing
, is.decreasing.on.y
Examples
is.decreasing.on.x(fun=function(x,y) 2*x+y, x.bound=c(0,2), y.bound=c(1,2), step=.2)
f = function(x,y) -x^2+y
is.decreasing.on.x(f, x.bound=c(0,2), y.bound=c(0,2))
is.decreasing.on.x(f, x.bound=c(-2,2), y.bound=c(0,2))
## The function is currently defined as
function (fun, x.bound = c(-1, 1), y.bound = c(-1, 1), step = 0.01)
{
y = seq(y.bound[1], y.bound[2], by = step)
for (i in 1:length(y)) {
g = function(x) fun(x, y[i])
if (is.decreasing(g, x.bound, step) == FALSE) {
return(FALSE)
}
}
return(TRUE)
}