peaks: Peaks Function (Matlab Style)

Description Usage Arguments Details Value Note See Also Examples

View source: R/meshgrid.R

Description

An example functions in two variables, with peaks.

Usage

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peaks(v = 49, w)

Arguments

v

vector, whose length will be used, or a natural number.

w

another vector, will be used in meshgrid(x,y).

Details

peaks is a function of two variables, obtained by translating and scaling Gaussian distributions, which is useful for demonstrating three-dimensional plots.

Value

Returns three matrices as a list with X, Y, and Z components, the first two being the result of the meshgrid function, and Z the application of the following function at the points of X and Y:

z <- 3 * (1-x)^2 * exp(-(x^2) - (y+1)^2) - 10 * (x/5 - x^3 - y^5) * exp(-x^2 - y^2) - 1/3 * exp(-(x+1)^2 - y^2)

Note

The variant that peaks() will display the 3-dim. graph as in Matlab is not yet implemented.

See Also

meshgrid

Examples

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peaks(3)
## Not run: 
P <- peaks()
x <- P$X[1,]; y <- P$Y[, 1]
persp(x, y, P$Z)

## End(Not run)

Example output

$X
     [,1] [,2] [,3]
[1,]   -3    0    3
[2,]   -3    0    3
[3,]   -3    0    3

$Y
     [,1] [,2] [,3]
[1,]   -3   -3   -3
[2,]    0    0    0
[3,]    3    3    3

$Z
              [,1]       [,2]          [,3]
[1,]  6.671280e-05 -0.2449540 -5.864188e-06
[2,] -3.650620e-02  0.9810118  3.312495e-02
[3,]  3.223536e-05  0.2998710  4.102973e-05

pracma documentation built on Jan. 30, 2018, 3:01 a.m.