fsurf

Plot 3-D surface

Syntax

fsurf(f)

fsurf(f,[min max])

fsurf(f,[xmin xmax ymin ymax])

fsurf(funx,funy,funz)

fsurf(funx,funy,funz,[uvmin uvmax])

fsurf(funx,funy,funz,[umin umax vmin vmax])

fsurf(___,LineSpec)

fsurf(___,Name,Value)

fsurf(ax,___)

fs = fsurf(___)

Description

fsurf(f) creates a surface plot of the symbolic expression f(x,y) over the default interval [-5 5] for x and y.

fsurf(f,[min max]) plots f(x,y) over the interval [min max] for x and y.

fsurf(f,[xmin xmax ymin ymax]) plots f(x,y) over the interval [xmin xmax] for x and [ymin ymax] for y. The fsurf function uses symvar to order the variables and assign intervals.

fsurf(funx,funy,funz) plots the parametric surface x = x(u,v), y = y(u,v), z = z(u,v) over the interval [-5 5] for u and v.

fsurf(funx,funy,funz,[uvmin uvmax]) plots the parametric surface x = x(u,v), y = y(u,v), z = z(u,v) over the interval [uvmin uvmax] for u and v.

fsurf(funx,funy,funz,[umin umax vmin vmax]) plots the parametric surface x = x(u,v), y = y(u,v), z = z(u,v) over the interval [umin umax] for u and [vmin vmax] for v. The fsurf function uses symvar to order the parametric variables and assign intervals.

fsurf(___,LineSpec) uses LineSpec to set the line style, marker symbol, and face color. Use this option after any of the previous input argument combinations.

fsurf(___,Name,Value) specifies line properties using one or more Name,Value pair arguments. Use this option after any of the input argument combinations in the previous syntaxes.

fsurf(ax,___) plots into the axes with the object ax instead of the current axes object gca.

fs = fsurf(___) returns a function surface object or parameterized function surface object, depending on the type of surface. Use the object to query and modify properties of a specific surface. For details, see FunctionSurface Properties and ParameterizedFunctionSurface Properties.

Examples

3-D Surface Plot of Symbolic Expression

Plot the input $$\sin (x)+\cos (y)$$ over the default range $$-5<x<5$$ and $$-5<y<5$$.

syms x y
fsurf(sin(x)+cos(y))

3-D Surface Plot of Symbolic Function

Plot the real part of $${tan}^{-1}(x+iy)$$ over the default range $$-5<x<5$$ and $$-5<y<5$$.

syms f(x,y)
f(x,y) = real(atan(x + i*y));
fsurf(f)

Specify Plotting Interval of Surface Plot

Plot $$\sin (x)+\cos (y)$$ over $$-\pi <x<\pi$$ and $$-5<y<5$$ by specifying the plotting interval as the second argument of fsurf.

syms x y
f = sin(x) + cos(y);
fsurf(f, [-pi pi -5 5])

Parameterized Surface Plot

Plot the parameterized surface

$$\begin{array}{c}x=r\cos (s)\sin (t)\\ y=r\sin (s)\sin (t)\\ z=r\cos (t)\\ wherer=2+\sin (7s+5t)\end{array}$$

for $$0<s<2\pi$$ and $$0<t<\pi$$.

Improve the plot's appearance by using camlight.

syms s t
r = 2 + sin(7*s + 5*t);
x = r*cos(s)*sin(t);
y = r*sin(s)*sin(t);
z = r*cos(t);
fsurf(x, y, z, [0 2*pi 0 pi])
camlight
view(46,52)

Surface Plot of Piecewise Expression

Plot the piecewise expression of the Klein bottle

$$\begin{array}{l}\mathit{x}\left(\mathit{u},\mathit{v}\right)=\{\begin{array}{cc}-4\cos \left(\mathit{u}\right)\left[1+\sin \left(\mathit{u}\right)\right]-\mathit{r}\left(\mathit{u}\right)\cos \left(\mathit{u}\right)\cos \left(\mathit{v}\right)& 0<\mathit{u}\le \pi \\ -4\cos \left(\mathit{u}\right)\left[1+\sin \left(\mathit{u}\right)\right]+\mathit{r}\left(\mathit{u}\right)\cos \left(\mathit{v}\right)& \pi <\mathit{u}<\mathrm{2}\pi \end{array}\\ \mathit{y}\left(\mathit{u},\mathit{v}\right)=\mathit{r}\left(\mathit{u}\right)\sin \left(\mathit{v}\right)\\ \mathit{z}\left(\mathit{u},\mathit{v}\right)=\{\begin{array}{cc}-14\sin \left(\mathit{u}\right)-\mathit{r}\left(\mathit{u}\right)\sin \left(\mathit{u}\right)\cos \left(\mathit{v}\right)& 0<\mathit{u}\le \pi \\ -14\sin \left(\mathit{u}\right)& \pi <\mathit{u}<\mathrm{2}\pi \end{array}\\ \mathrm{where}\mathit{r}\left(\mathit{u}\right)=4-2\cos \left(\mathit{u}\right)\end{array}$$

for $0<\mathit{u}<2\pi$ and $0<\mathit{v}<2\pi$.

Show that the Klein bottle has only a one-sided surface.

syms u v;
r = @(u) 4 - 2*cos(u);
x = piecewise(u <= pi, -4*cos(u)*(1+sin(u)) - r(u)*cos(u)*cos(v),...
    u > pi, -4*cos(u)*(1+sin(u)) + r(u)*cos(v));
y = r(u)*sin(v);
z = piecewise(u <= pi, -14*sin(u) - r(u)*sin(u)*cos(v),...
    u > pi, -14*sin(u));
h = fsurf(x,y,z, [0 2*pi 0 2*pi]);

Add Title and Axis Labels and Format Ticks

For $$x$$ and $$y$$ from $$-2\pi$$ to $$2\pi$$, plot the 3-D surface $$y\sin (x)-x\cos (y)$$. Add a title and axis labels.

Create the x-axis ticks by spanning the x-axis limits at intervals of pi/2. Convert the axis limits to precise multiples of pi/2 by using round and get the symbolic tick values in S. Display these ticks by using the XTick property. Create x-axis labels by using arrayfun to apply texlabel to S. Display these labels by using the XTickLabel property. Repeat these steps for the y-axis.

To use LaTeX in plots, see latex.

syms x y
fsurf(y.*sin(x)-x.*cos(y), [-2*pi 2*pi])
title('ysin(x) - xcos(y) for x and y in [-2\pi,2\pi]')
xlabel('x')
ylabel('y')
zlabel('z')

ax = gca;
S = sym(ax.XLim(1):pi/2:ax.XLim(2));
S = sym(round(vpa(S/pi*2))*pi/2);
ax.XTick = double(S);
ax.XTickLabel = arrayfun(@texlabel,S,'UniformOutput',false);

S = sym(ax.YLim(1):pi/2:ax.YLim(2));
S = sym(round(vpa(S/pi*2))*pi/2);
ax.YTick = double(S);
ax.YTickLabel = arrayfun(@texlabel,S,'UniformOutput',false);

Line Style and Width for Surface Plot

Plot the parametric surface $$x=s\sin (t)$$, $$y=-s\cos (t)$$, $$z=t$$ with different line styles for different values of $$t$$. For $$-5<t<-2$$, use a dashed line with green dot markers. For $$-2<t<2$$, use a LineWidth of 1 and a green face color. For $$2<t<5$$, turn off the lines by setting EdgeColor to none.

syms s t
fsurf(s*sin(t),-s*cos(t),t,[-5 5 -5 -2],'--.','MarkerEdgeColor','g')
hold on
fsurf(s*sin(t),-s*cos(t),t,[-5 5 -2 2],'LineWidth',1,'FaceColor','g')
fsurf(s*sin(t),-s*cos(t),t,[-5 5 2 5],'EdgeColor','none')

Modify Surface After Creation

Plot the parametric surface

$$\begin{array}{c}x=e^{-|u|/10}\sin (5|v|)\\ y=e^{-|u|/10}\cos (5|v|)\\ z=u.\end{array}$$

Specify an output to make fcontour return the plot object.

syms u v
x = exp(-abs(u)/10).*sin(5*abs(v));
y = exp(-abs(u)/10).*cos(5*abs(v));
z = u;
fs = fsurf(x,y,z)

fs = 
  ParameterizedFunctionSurface with properties:

    XFunction: exp(-abs(u)/10)*sin(5*abs(v))
    YFunction: exp(-abs(u)/10)*cos(5*abs(v))
    ZFunction: u
    EdgeColor: [0 0 0]
    LineStyle: '-'
    FaceColor: 'interp'

  Show all properties

Change the range of u to [-30 30] by using the URange property of fs. Set the line color to blue by using the EdgeColor property and specify white, dot markers by using the Marker and MarkerEdgeColor properties.

fs.URange = [-30 30];
fs.EdgeColor = 'b';
fs.Marker = '.';
fs.MarkerEdgeColor = 'w';

Multiple Surface Plots and Transparent Surfaces

Plot multiple surfaces using vector input to fsurf. Alternatively, use hold on to plot successively on the same figure. When displaying multiple surfaces on the same figure, transparency is useful. Adjust the transparency of surface plots by using the FaceAlpha property. FaceAlpha varies from 0 to 1, where 0 is full transparency and 1 is no transparency.

Plot the planes $$x+y$$ and $$x-y$$ using vector input to fsurf. Show both planes by making them half transparent using FaceAlpha.

syms x y
h = fsurf([x+y x-y]);
h(1).FaceAlpha = 0.5;
h(2).FaceAlpha = 0.5;
title('Planes (x+y) and (x-y) at half transparency')

Control Resolution of Surface Plot

Control the resolution of a surface plot using the 'MeshDensity' option. Increasing 'MeshDensity' can make smoother, more accurate plots while decreasing it can increase plotting speed.

Divide a figure into two using subplot. In the first subplot, plot the parametric surface $$x=\sin (s)$$, $$y=\cos (s)$$, and $$z=(t/10)\sin (1/s)$$. The surface has a large gap. Fix this issue by increasing the 'MeshDensity' to 40 in the second subplot. fsurf fills the gap showing that by increasing 'MeshDensity' you increased the plot's resolution.

syms s t

subplot(2,1,1)
fsurf(sin(s), cos(s), t/10.*sin(1./s))
view(-172,25)
title('Default MeshDensity = 35')

subplot(2,1,2)
fsurf(sin(s), cos(s), t/10.*sin(1./s),'MeshDensity',40)
view(-172,25)
title('Increased MeshDensity = 40')

Show Contours Below Surface Plot

Show contours for the surface plot of the expression f by setting the 'ShowContours' option to 'on'.

syms x y
f = 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);
fsurf(f,[-3 3],'ShowContours','on')

Create Animation of Surface Plots

Create an animation of surface plots by changing the displayed expression using the Function, XFunction, YFunction, and ZFunction properties, and then use drawnow to update the plot. To export to GIF, see imwrite.

By varying the variable from 1 to 3, animate the parametric surface

for and . Increase plotting speed by reducing MeshDensity to 9.

syms s t
h = fsurf(t.*sin(s), cos(s), sin(1./s), [-0.1 0.1 0 1]);
h.MeshDensity = 9;
for i=1:0.1:3
    h.ZFunction = sin(i./s);
    drawnow
end

Improve Appearance of Surface Plot

Create a symbolic expression f for the function

$$f=3(1-x{)}^2\exp (-(x^2)-(y+1{)}^2)-10(x/5-x^3-y^5)\exp (-x^2-y^2)-1/3\exp (-(x+1{)}^2-y^2).$$

Plot the expression f as a surface. Improve the appearance of the surface plot by using the properties of the handle returned by fsurf, the lighting properties, and the colormap.

Create a light by using camlight. Increase brightness by using brighten. Remove the lines by setting EdgeColor to 'none'. Increase the ambient light using AmbientStrength. For details, see Lighting, Transparency, and Shading. Turn the axes box on. For the title, convert f to LaTeX using latex. Finally, to improve the appearance of the axes ticks, axes labels, and title, set 'Interpreter' to 'latex'.

syms x y
f = 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);
h = fsurf(f,[-3 3]);

camlight(110,70)
brighten(0.6)
h.EdgeColor = 'none';
h.AmbientStrength = 0.4;

a = gca;
a.TickLabelInterpreter = 'latex';
a.Box = 'on';
a.BoxStyle = 'full';

xlabel('$x$','Interpreter','latex')
ylabel('$y$','Interpreter','latex')
zlabel('$z$','Interpreter','latex')
title_latex = ['$' latex(f) '$'];
title(title_latex,'Interpreter','latex')

Surface Plot with Bounded Plane

Plot a cylindrical shell bounded below by the $$x-y$$ plane and above by the plane $$z=x+2$$.

syms r t u
fsurf(cos(t),sin(t),u*(cos(t)+2),[0 2*pi 0 1])
hold on;

Add a surface plot of the plane $$z=x+2$$.

fsurf(r*cos(t),r*sin(t),r*cos(t)+2,[0 1 0 2*pi])

Apply Rotation and Translation to Surface Plot

Apply rotation and translation to the surface plot of a torus.

A torus can be defined parametrically by

$$\begin{array}{l}\mathit{x}\left(\theta ,\phi \right)=\left(\mathit{R}+\mathit{a}\cos \theta \right)\cos \phi \\ \mathit{y}\left(\theta ,\phi \right)=\left(\mathit{R}+\mathit{a}\cos \theta \right)\sin \phi \\ \mathit{z}\left(\theta ,\phi \right)=\mathit{a}\sin \phi \end{array}$$

where

• $\theta$ is the polar angle and $\phi$ is the azimuthal angle

• $\mathit{a}$ is the radius of the tube

• $\mathit{R}$ is the distance from the center of the tube to the center of the torus

Define the values for $$a$$ and $$R$$ as 1 and 5, respectively. Plot the torus using fsurf.

syms theta phi
a = 1;
R = 4;
x = (R + a*cos(theta))*cos(phi);
y = (R + a*cos(theta))*sin(phi);
z = a*sin(theta);
fsurf(x,y,z,[0 2*pi 0 2*pi])
hold on

Apply rotation to the torus around the $$x$$-axis. Define the rotation matrix. Rotate the torus by 90 degrees or $$\pi /2$$ radians.

alpha = pi/2;
Rx = [1 0 0;
      0 cos(alpha) -sin(alpha);
      0 sin(alpha) cos(alpha)];
r = [x; y; z];
r_90 = Rx*r;

Shift the center of the torus by 5 along the $$x$$-axis. Add a second plot of the rotated and translated torus to the existing graph.

fsurf(r_90(1)+5,r_90(2),r_90(3))
axis([-5 10 -5 10 -5 5])
hold off

Input Arguments

f — 3-D expression or function to be plotted

symbolic expression | symbolic function

Expression or function to be plotted, specified as a symbolic expression or function.

[min max] — Plotting interval for x- and y-axes

[–5 5] (default) | vector of two numbers

Plotting interval for x- and y-axes, specified as a vector of two numbers. The default is [-5 5].

[xmin xmax ymin ymax] — Plotting interval for x- and y-axes

[–5 5 –5 5] (default) | vector of four numbers

Plotting interval for x- and y-axes, specified as a vector of four numbers. The default is [-5 5 -5 5].

funx,funy,funz — Parametric functions of u and v

symbolic expressions | symbolic functions

Parametric functions of u and v, specified as a symbolic expression or function.

[uvmin uvmax] — Plotting interval for u and v

[–5 5] (default) | vector of two numbers

Plotting interval for u and v axes, specified as a vector of two numbers. The default is [-5 5].

[umin umax vmin vmax] — Plotting interval for u and v

[–5 5 –5 5] (default) | vector of four numbers

Plotting interval for u and v, specified as a vector of four numbers. The default is [-5 5 -5 5].

ax — Axes object

axes object

Axes object. If you do not specify an axes object, then fsurf uses the current axes.

LineSpec — Line style, marker, and color

string scalar | character vector

Line style, marker, and color, specified as a string scalar or character vector containing symbols. The symbols can appear in any order. You do not need to specify all three characteristics (line style, marker, and color). For example, if you omit the line style and specify the marker, then the plot shows only the marker and no line.

Example: "--or" is a red dashed line with circle markers.

Line Style	Description	Resulting Line
"-"	Solid line
"--"	Dashed line
":"	Dotted line
"-."	Dash-dotted line

Marker	Description	Resulting Marker
"o"	Circle
"+"	Plus sign
"*"	Asterisk
"."	Point
"x"	Cross
"_"	Horizontal line
"|"	Vertical line
"square"	Square
"diamond"	Diamond
"^"	Upward-pointing triangle
"v"	Downward-pointing triangle
">"	Right-pointing triangle
"<"	Left-pointing triangle
"pentagram"	Pentagram
"hexagram"	Hexagram

Color Name	Short Name	RGB Triplet	Appearance
"red"	"r"	[1 0 0]
"green"	"g"	[0 1 0]
"blue"	"b"	[0 0 1]
"cyan"	"c"	[0 1 1]
"magenta"	"m"	[1 0 1]
"yellow"	"y"	[1 1 0]
"black"	"k"	[0 0 0]
"white"	"w"	[1 1 1]

Name-Value Arguments

Specify optional pairs of arguments as Name1=Value1,...,NameN=ValueN, where Name is the argument name and Value is the corresponding value. Name-value arguments must appear after other arguments, but the order of the pairs does not matter.

Before R2021a, use commas to separate each name and value, and enclose Name in quotes.

Example: 'Marker','o','MarkerFaceColor','red'

The properties listed here are only a subset. For a complete list, see FunctionSurface Properties.

MeshDensity — Number of evaluation points per direction

35 (default) | number

Number of evaluation points per direction, specified as a number. The default is 35. Because fsurf objects use adaptive evaluation, the actual number of evaluation points is greater.

Example: 100

ShowContours — Display contour plot under plot

'off' (default) | on/off logical value

Display contour plot under plot, specified as 'on' or 'off', or as numeric or logical 1 (true) or 0 (false). A value of 'on' is equivalent to true, and 'off' is equivalent to false. Thus, you can use the value of this property as a logical value. The value is stored as an on/off logical value of type matlab.lang.OnOffSwitchState.

EdgeColor — Line color

[0 0 0] (default) | 'interp' | RGB triplet | hexadecimal color code | 'r' | 'g' | 'b' | ...

Line color, specified as 'interp', an RGB triplet, a hexadecimal color code, a color name, or a short name. The default RGB triplet value of [0 0 0] corresponds to black. The 'interp' value colors the edges based on the ZData values.

For a custom color, specify an RGB triplet or a hexadecimal color code.

• An RGB triplet is a three-element row vector whose elements specify the intensities of the red, green, and blue components of the color. The intensities must be in the range [0,1], for example, [0.4 0.6 0.7].

• A hexadecimal color code is a string scalar or character vector that starts with a hash symbol (#) followed by three or six hexadecimal digits, which can range from 0 to F. The values are not case sensitive. Therefore, the color codes "#FF8800", "#ff8800", "#F80", and "#f80" are equivalent.

Alternatively, you can specify some common colors by name. This table lists the named color options, the equivalent RGB triplets, and the hexadecimal color codes.

Color Name	Short Name	RGB Triplet	Hexadecimal Color Code	Appearance
"red"	"r"	[1 0 0]	"#FF0000"
"green"	"g"	[0 1 0]	"#00FF00"
"blue"	"b"	[0 0 1]	"#0000FF"
"cyan"	"c"	[0 1 1]	"#00FFFF"
"magenta"	"m"	[1 0 1]	"#FF00FF"
"yellow"	"y"	[1 1 0]	"#FFFF00"
"black"	"k"	[0 0 0]	"#000000"
"white"	"w"	[1 1 1]	"#FFFFFF"
"none"	Not applicable	Not applicable	Not applicable	No color

This table lists the default color palettes for plots in the light and dark themes.

Palette	Palette Colors
"gem" — Light theme default Before R2025a: Most plots use these colors by default.
"glow" — Dark theme default

You can get the RGB triplets and hexadecimal color codes for these palettes using the orderedcolors and rgb2hex functions. For example, get the RGB triplets for the "gem" palette and convert them to hexadecimal color codes.

RGB = orderedcolors("gem");
H = rgb2hex(RGB);

Before R2023b: Get the RGB triplets using RGB = get(groot,"FactoryAxesColorOrder").

Before R2024a: Get the hexadecimal color codes using H = compose("#%02X%02X%02X",round(RGB*255)).

LineStyle — Line style

"-" (default) | "--" | ":" | "-." | "none"

Line style, specified as one of the options listed in this table.

Line Style	Description	Resulting Line
"-"	Solid line
"--"	Dashed line
":"	Dotted line
"-."	Dash-dotted line
"none"	No line	No line

LineWidth — Line width

0.5 (default) | positive value

Line width, specified as a positive value in points, where 1 point = 1/72 of an inch. If the line has markers, then the line width also affects the marker edges.

The line width cannot be thinner than the width of a pixel. If you set the line width to a value that is less than the width of a pixel on your system, the line displays as one pixel wide.

Marker — Marker symbol

"none" (default) | "o" | "+" | "*" | "." | ...

Marker symbol, specified as one of the values listed in this table. By default, the object does not display markers. Specifying a marker symbol adds markers at each data point or vertex.

Marker	Description	Resulting Marker
"o"	Circle
"+"	Plus sign
"*"	Asterisk
"."	Point
"x"	Cross
"_"	Horizontal line
"|"	Vertical line
"square"	Square
"diamond"	Diamond
"^"	Upward-pointing triangle
"v"	Downward-pointing triangle
">"	Right-pointing triangle
"<"	Left-pointing triangle
"pentagram"	Pentagram
"hexagram"	Hexagram
"none"	No markers	Not applicable

MarkerEdgeColor — Marker outline color

'auto' (default) | RGB triplet | hexadecimal color code | 'r' | 'g' | 'b' | ...

Marker outline color, specified as 'auto', an RGB triplet, a hexadecimal color code, a color name, or a short name. The default value of 'auto' uses the same color as the EdgeColor property.

For a custom color, specify an RGB triplet or a hexadecimal color code.

• An RGB triplet is a three-element row vector whose elements specify the intensities of the red, green, and blue components of the color. The intensities must be in the range [0,1], for example, [0.4 0.6 0.7].

• A hexadecimal color code is a string scalar or character vector that starts with a hash symbol (#) followed by three or six hexadecimal digits, which can range from 0 to F. The values are not case sensitive. Therefore, the color codes "#FF8800", "#ff8800", "#F80", and "#f80" are equivalent.

Alternatively, you can specify some common colors by name. This table lists the named color options, the equivalent RGB triplets, and the hexadecimal color codes.

Color Name	Short Name	RGB Triplet	Hexadecimal Color Code	Appearance
"red"	"r"	[1 0 0]	"#FF0000"
"green"	"g"	[0 1 0]	"#00FF00"
"blue"	"b"	[0 0 1]	"#0000FF"
"cyan"	"c"	[0 1 1]	"#00FFFF"
"magenta"	"m"	[1 0 1]	"#FF00FF"
"yellow"	"y"	[1 1 0]	"#FFFF00"
"black"	"k"	[0 0 0]	"#000000"
"white"	"w"	[1 1 1]	"#FFFFFF"
"none"	Not applicable	Not applicable	Not applicable	No color

This table lists the default color palettes for plots in the light and dark themes.

Palette	Palette Colors
"gem" — Light theme default Before R2025a: Most plots use these colors by default.
"glow" — Dark theme default

You can get the RGB triplets and hexadecimal color codes for these palettes using the orderedcolors and rgb2hex functions. For example, get the RGB triplets for the "gem" palette and convert them to hexadecimal color codes.

RGB = orderedcolors("gem");
H = rgb2hex(RGB);

Before R2023b: Get the RGB triplets using RGB = get(groot,"FactoryAxesColorOrder").

Before R2024a: Get the hexadecimal color codes using H = compose("#%02X%02X%02X",round(RGB*255)).

Example: [0.5 0.5 0.5]

Example: 'blue'

Example: '#D2F9A7'

MarkerFaceColor — Marker fill color

"none" (default) | "auto" | RGB triplet | hexadecimal color code | "r" | "g" | "b" | ...

Marker fill color, specified as "auto", an RGB triplet, a hexadecimal color code, a color name, or a short name. The "auto" value uses the same color as the MarkerEdgeColor property.

For a custom color, specify an RGB triplet or a hexadecimal color code.

• An RGB triplet is a three-element row vector whose elements specify the intensities of the red, green, and blue components of the color. The intensities must be in the range [0,1], for example, [0.4 0.6 0.7].

• A hexadecimal color code is a string scalar or character vector that starts with a hash symbol (#) followed by three or six hexadecimal digits, which can range from 0 to F. The values are not case sensitive. Therefore, the color codes "#FF8800", "#ff8800", "#F80", and "#f80" are equivalent.

Alternatively, you can specify some common colors by name. This table lists the named color options, the equivalent RGB triplets, and the hexadecimal color codes.

Color Name	Short Name	RGB Triplet	Hexadecimal Color Code	Appearance
"red"	"r"	[1 0 0]	"#FF0000"
"green"	"g"	[0 1 0]	"#00FF00"
"blue"	"b"	[0 0 1]	"#0000FF"
"cyan"	"c"	[0 1 1]	"#00FFFF"
"magenta"	"m"	[1 0 1]	"#FF00FF"
"yellow"	"y"	[1 1 0]	"#FFFF00"
"black"	"k"	[0 0 0]	"#000000"
"white"	"w"	[1 1 1]	"#FFFFFF"
"none"	Not applicable	Not applicable	Not applicable	No color

This table lists the default color palettes for plots in the light and dark themes.

Palette	Palette Colors
"gem" — Light theme default Before R2025a: Most plots use these colors by default.
"glow" — Dark theme default

You can get the RGB triplets and hexadecimal color codes for these palettes using the orderedcolors and rgb2hex functions. For example, get the RGB triplets for the "gem" palette and convert them to hexadecimal color codes.

RGB = orderedcolors("gem");
H = rgb2hex(RGB);

Before R2023b: Get the RGB triplets using RGB = get(groot,"FactoryAxesColorOrder").

Before R2024a: Get the hexadecimal color codes using H = compose("#%02X%02X%02X",round(RGB*255)).

Example: [0.3 0.2 0.1]

Example: "green"

Example: "#D2F9A7"

MarkerSize — Marker size

6 (default) | positive value

Marker size, specified as a positive value in points, where 1 point = 1/72 of an inch.

Output Arguments

fs — One or more objects

scalar | vector

One or more objects, returned as a scalar or a vector. The object is either a function surface object or parameterized surface object, depending on the type of plot. You can use these objects to query and modify properties of a specific line. For details, see FunctionSurface Properties and ParameterizedFunctionSurface Properties.

Algorithms

fsurf assigns the symbolic variables in f to the x-axis, then the y-axis, and symvar determines the order of the variables to be assigned. Therefore, variable and axis names might not correspond. To force fsurf to assign x or y to its corresponding axis, create the symbolic function to plot, then pass the symbolic function to fsurf.

For example, the following code plots f(x,y) = sin(y) in two ways. The first way forces the waves to oscillate with respect to the y-axis. In other words, the first plot assigns the y variable to the corresponding y-axis. The second plot assigns y to the x-axis because it is the first (and only) variable in the symbolic function.

syms x y;
f(x,y) = sin(y);

figure;
subplot(2,1,1)
fsurf(f);
subplot(2,1,2)
fsurf(f(x,y)); % Or fsurf(sin(y));

Version History

Introduced in R2016a