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**Class: **TriScatteredInterp

(Not recommended) Interpolate scattered data

`TriScatteredInterp`

is not recommended. Use `scatteredInterpolant`

instead.

`F = TriScatteredInterp()`

F = TriScatteredInterp(X, V)

F = TriScatteredInterp(X, Y, V)

F
= TriScatteredInterp(X, Y, Z, V)

F = TriScatteredInterp(DT, V)

F = TriScatteredInterp(..., method)

`F = TriScatteredInterp()`

creates an empty
scattered data interpolant. This can subsequently be initialized with
sample data points and values (`Xdata`

, `Vdata`

)
via `F.X = Xdata`

and `F.V = Vdata`

.

`F = TriScatteredInterp(X, V)`

creates an
interpolant that fits a surface of the form `V = F(X)`

to
the scattered data in (`X`

, `V`

). `X`

is
a matrix of size `mpts`

-by-`ndim`

,
where `mpts`

is the number of points and `ndim`

is
the dimension of the space where the points reside (`ndim`

is
2 or 3). The column vector `V`

defines the values
at `X`

, where the length of `V`

equals `mpts`

.

`F = TriScatteredInterp(X, Y, V)`

and ```
F
= TriScatteredInterp(X, Y, Z, V)
```

allow the data point
locations to be specified in alternative column vector format when
working in 2-D and 3-D.

`F = TriScatteredInterp(DT, V)`

uses the
specified `DelaunayTri`

object `DT`

as
a basis for computing the interpolant. `DT`

is a
Delaunay triangulation of the scattered data locations, `DT.X`

.
The matrix `DT.X`

is of size `mpts`

-by-`ndim`

,
where `mpts`

is the number of points and `ndim`

is
the dimension of the space where the points reside, ```
2 <=
ndim <= 3
```

. `V`

is a column vector that
defines the values at `DT.X`

, where the length of `V`

equals `mpts`

.

`F = TriScatteredInterp(..., method)`

allows
selection of the technique `method`

used to interpolate
the data.

`X` | Matrix of size `mpts` -by-`ndim` ,
where `mpts` is the number of points and `ndim` is
the dimension of the space where the points reside. Input may also
be specified as column vectors (`X` , `Y` )
or (`X` , `Y` , `Z` ) | |

`V` | Column vector that
defines the values at `X` , where the length of `V` equals `mpts` . | |

`DT` | Delaunay triangulation of the scattered data locations | |

`method` | `natural` | Natural neighbor interpolation |

`linear` | Linear interpolation (default) | |

`nearest` | Nearest-neighbor interpolation |

`F` | Creates an interpolant that fits a surface of the form ```
V
= F(X)
``` to the scattered data. |

To evaluate the interpolant, express the statement in Monge's
form `Vq = F(Xq)`

, `Vq = F(Xq,Yq)`

,
or `Vq = F(Xq,Yq,Zq)`

where `Vq`

is
the value of the interpolant at the query location and `Xq`

, `Yq`

,
and `Zq`

are the vectors of point locations.

Create a data set:

x = rand(100,1)*4-2; y = rand(100,1)*4-2; z = x.*exp(-x.^2-y.^2);

F = TriScatteredInterp(x,y,z);

`(qx, qy)`

. The
corresponding value at these locations is `qz`

.ti = -2:.25:2; [qx,qy] = meshgrid(ti,ti); qz = F(qx,qy); mesh(qx,qy,qz); hold on; plot3(x,y,z,'o');

`delaunayTriangulation`

| `interp1`

| `interp2`

| `interp3`

| `meshgrid`

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