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Deformation Gradient Tensor

Usage

is.defgrad(x)

as.defgrad(object)

defgrad(x, ...)

defgrad_from_ratio(Rxy = 1, Ryz = 1)

# S3 method for class 'Pair'
defgrad(x, ...)

defgrad_from_vectors(v1, v2)

defgrad_from_axisangle(axis, angle)

defgrad_from_comp(
  xx = 1,
  xy = 0,
  xz = 0,
  yx = 0,
  yy = 1,
  yz = 0,
  zx = 0,
  zy = 0,
  zz = 1
)

# Default S3 method
defgrad(x, ...)

# S3 method for class 'velgrad'
defgrad(x, time, steps)

Arguments

x

object of class "Pair", "velgrad" or 3x3 "matrix"

object

3x3 "matrix"

...

parameters passed to function call

Rxy, Ryz

numeric. the XY and YZ strain ratio to create a strain tensor with axial stretches.Values must be greater than or equal to 1.

v1, v2

spherical objects. Deformation gradient results from the rotation around axis perpendicular to both vectors to rotate v1 to v2.

axis, angle

rotation axis and angle, axis can be an object of class "Vec3", "Line", "Ray", or "Plane", or a three-element vector. Angle in degrees when axis is a object of class "Line", "Ray", or "Plane", and radians otherwise.

xx, xy, xz, yx, yy, yz, zx, zy, zz

numeric. Directly specify components of the tensor. Identity matrix by default.

time

numeric. Total time (default is 1)

steps

numeric. Time increments (default is 1)

Value

3x3 matrix.

Examples

defgrad_from_ratio(2, 3)
#>          [,1]     [,2]      [,3]
#> [1,] 2.289428 0.000000 0.0000000
#> [2,] 0.000000 1.144714 0.0000000
#> [3,] 0.000000 0.000000 0.3815714
#> attr(,"class")
#> [1] "matrix"  "array"   "defgrad"
defgrad_from_axisangle(Line(120, 50), 60)
#>            [,1]       [,2]      [,3]
#> [1,]  0.8798642 -0.4069917 0.2453504
#> [2,]  0.3590528  0.9075417 0.2178283
#> [3,] -0.3113200 -0.1035655 0.9446449
#> attr(,"class")
#> [1] "matrix"  "array"   "defgrad"
defgrad_from_vectors(Line(120, 50), Line(270, 80))
#>             [,1]       [,2]       [,3]
#> [1,]  0.86775875 0.01649708  0.2175641
#> [2,]  0.08991349 0.77796344 -0.4437182
#> [3,] -0.19880103 0.45243581  0.7540121
#> attr(,"class")
#> [1] "matrix"  "array"   "defgrad"
defgrad(Pair(40, 20, 75, 16))
#>           [,1]       [,2]       [,3]
#> [1,] 0.2487928 -0.9331095 -0.2620026
#> [2,] 0.9285075  0.3060065 -0.2198463
#> [3,] 0.2756374 -0.1885752  0.9396926
#> attr(,"class")
#> [1] "matrix"  "array"   "defgrad"