Documentation

This is machine translation

Translated by Microsoft
Mouseover text to see original. Click the button below to return to the English verison of the page.

Note: This page has been translated by MathWorks. Please click here
To view all translated materals including this page, select Japan from the country navigator on the bottom of this page.

curl

Compute curl and angular velocity of vector field

Syntax

[curlx,curly,curlz,cav] = curl(X,Y,Z,U,V,W)
[curlx,curly,curlz,cav] = curl(U,V,W)
[curlz,cav]= curl(X,Y,U,V)
[curlz,cav]= curl(U,V)
[curlx,curly,curlz] = curl(...)
[curlx,curly] = curl(...)
cav = curl(...)

Description

[curlx,curly,curlz,cav] = curl(X,Y,Z,U,V,W) computes the curl (curlx, curly, curlz) and angular velocity (cav) perpendicular to the flow (in radians per time unit) of a 3-D vector field U, V, W.

The arrays X, Y, and Z, which define the coordinates for U, V, and W, must be monotonic, but do not need to be uniformly spaced. X, Y, and Z must have the same number of elements, as if produced by meshgrid.

[curlx,curly,curlz,cav] = curl(U,V,W) assumes X, Y, and Z are determined by the expression

[X Y Z] = meshgrid(1:n,1:m,1:p)

where [m,n,p] = size(U).

[curlz,cav]= curl(X,Y,U,V) computes the curl z-component and the angular velocity perpendicular to z (in radians per time unit) of a 2-D vector field U, and V.

The arrays X and Y, which define the coordinates for U and V, must be monotonic, but do not need to be uniformly spaced. X and Y must have the same number of elements, as if produced by meshgrid.

[curlz,cav]= curl(U,V) assumes X and Y are determined by the expression

[X Y] = meshgrid(1:n,1:m)

where [m,n] = size(U).

[curlx,curly,curlz] = curl(...), [curlx,curly] = curl(...) returns only the curl.

cav = curl(...) returns only the curl angular velocity.

Examples

collapse all

Use colored slice planes to display the curl angular velocity at specified locations in the vector field.

load wind
cav = curl(x,y,z,u,v,w);
h = slice(x,y,z,cav,[90 134],59,0); 
shading interp
daspect([1 1 1]); 
axis tight
colormap(hot(16));
camlight
set([h(1),h(2)],'ambientstrength',.6);

Display the curl angular velocity in one plane of the volume. Then plot the velocity vectors in the same plane.

load wind
k = 4;
x = x(:,:,k); 
y = y(:,:,k); 
u = u(:,:,k); 
v = v(:,:,k); 
cav = curl(x,y,u,v);
pcolor(x,y,cav); 
shading interp
hold on
quiver(x,y,u,v,'y');
hold off
colormap('copper');

Introduced before R2006a

Was this topic helpful?