fimplicit

Plot implicit function

collapse all in page

Syntax

Description

example

fimplicit(f) plots the implicit function defined by f(x,y) = 0 over the default interval [-5 5] for x and y.

example

fimplicit(f,interval) specifies the plotting interval for x and y.

fimplicit(ax,___) plots into the axes specified by ax instead of into the current axes. Specify the axes as the first input argument, prior to any of the previous input arguments.

example

fimplicit(___,LineSpec) specifies the line style, marker symbol, and line color. For example, '-r' plots a red line.

example

fimplicit(___,Name,Value) specifies line properties using one or more name-value pair arguments. For example, 'LineWidth',2 specifies a line width of 2 points.

example

fp = fimplicit(___) returns the implicit function line object. Use fp to access and modify properties of the line after it is created. For a list of properties, see Implicit Function Line Properties.

Examples

collapse all

Open Script

Plot the hyperbola described by the function $x^2 - y^2 - 1 = 0$ over the default interval of [-5 5] for x and y.

fimplicit(@(x,y) x.^2 - y.^2 - 1)

Open Script

Plot the function $x^2 + y^2 - 3 = 0$ over the intervals [-3 0] for x and [-2 2] for y.

f = @(x,y) x.^2 + y.^2 - 3;
fimplicit(f,[-3 0 -2 2])

Open Script

Plot two circles centered at (0,0) with different radius values. For the first circle, use a dotted, red line. For the second circle, use a dashed, green line with a line width of 2 points.

f1 = @(x,y) x.^2 + y.^2 - 1;
fimplicit(f1,':r')

hold on
f2 = @(x,y) x.^2 + y.^2 - 2;
fimplicit(f2,'--g','LineWidth',2)
hold off

Open Script

Plot the implicit function $y\sin(x) + x\cos(y) - 1 = 0$ and assign the implicit function line object to the variable fp.

fp = fimplicit(@(x,y) y.*sin(x) + x.*cos(y) - 1)

fp = 

  ImplicitFunctionLine with properties:

     Function: @(x,y)y.*sin(x)+x.*cos(y)-1
        Color: [0 0.4470 0.7410]
    LineStyle: '-'
    LineWidth: 0.5000

  Use GET to show all properties

Use fp to access and modify properties of the implicit function line object after it is created. For example, change the color, line style, and line width.

fp.Color = 'r';
fp.LineStyle = '--';
fp.LineWidth = 2;

Input Arguments

collapse all

Implicit function to plot, specified as a function handle to a named or anonymous function.

Specify a function of the form z = f(x,y). The function must accept two matrix input arguments and return a matrix output argument of the same size. Use array operators instead of matrix operators for the best performance. For example, use .* (times) instead of * (mtimes).

Example: fimplicit(@(x,y) x.^2 - y.^2 + 1)

Plotting interval for x and y, specified in one of these forms:

  • Two-element vector of the form [min max] — Use the same plotting interval of [min max] for both x and y.

  • Four-element vector of the form [xmin xmax ymin ymax] — Use different plotting intervals for x and y. Plot over the interval [xmin xmax] for x and [ymin ymax] for y.

Example: fimplicit(f,[-2 3 -5 0])

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

Example: fimplicit(f,'--or') plots a red, dashed line with circle markers.

Line StyleDescription
-Solid line (default)
--Dashed line
:Dotted line
-.Dash-dot line

MarkerDescription
oCircle
+Plus sign
*Asterisk
.Point
xCross
sSquare
dDiamond
^Upward-pointing triangle
vDownward-pointing triangle
>Right-pointing triangle
<Left-pointing triangle
pPentagram
hHexagram

ColorDescription

y

yellow

m

magenta

c

cyan

r

red

g

green

b

blue

w

white

k

black

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

Name-Value Pair Arguments

Specify optional comma-separated pairs of Name,Value arguments. Name is the argument name and Value is the corresponding value. Name must appear inside single quotes (' '). You can specify several name and value pair arguments in any order as Name1,Value1,...,NameN,ValueN.

Example: fimplicit(f,'MeshDensity',50,'LineWidth',2) specifies the number of evaluation points and the line width.

The implicit function line properties listed here are only a subset. For a complete list, see Implicit Function Line Properties.

collapse all

Number of evaluation points per direction, specified as a scalar.

Line color, specified as an RGB triplet, a character vector of a color name, or 'none'. If you specify the Color as 'none', then the line is invisible.

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]. This table lists the long and short color name options and the equivalent RGB triplet values.

Long NameShort NameRGB Triplet
'yellow''y'[1 1 0]
'magenta''m'[1 0 1]
'cyan''c'[0 1 1]
'red''r'[1 0 0]
'green''g'[0 1 0]
'blue''b'[0 0 1]
'white''w'[1 1 1]
'black''k'[0 0 0]

Example: 'blue'

Example: [0 0 1]

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

Line StyleDescriptionResulting Line
'-'Solid line

'--'Dashed line

':'Dotted line

'-.'Dash-dotted line

'none'No lineNo line

Line width, specified as a positive value in points. If the line has markers, then the line width also affects the marker edges.

Example: 0.75

Marker symbol, specified as one of the markers listed in this table. By default, the line does not have markers. Specifying a marker symbol adds markers at selected points along the line.

ValueDescription
'o'Circle
'+'Plus sign
'*'Asterisk
'.'Point
'x'Cross
'square' or 's'Square
'diamond' or 'd'Diamond
'^'Upward-pointing triangle
'v'Downward-pointing triangle
'>'Right-pointing triangle
'<'Left-pointing triangle
'pentagram' or 'p'Five-pointed star (pentagram)
'hexagram' or 'h'Six-pointed star (hexagram)
'none'No markers

Example: '+'

Example: 'diamond'

Marker size, specified as a positive value in points.

Example: 10

Marker outline color, specified as one of these values:

  • 'auto' — Use the same color specified in the Color property.

  • 'none' — Use no color, which makes unfilled markers invisible.

  • RGB triplet or character vector of a color name — Use the specified color.

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]. This table lists the long and short color name options and the equivalent RGB triplet values.

Long NameShort NameRGB Triplet
'yellow''y'[1 1 0]
'magenta''m'[1 0 1]
'cyan''c'[0 1 1]
'red''r'[1 0 0]
'green''g'[0 1 0]
'blue''b'[0 0 1]
'white''w'[1 1 1]
'black''k'[0 0 0]

Example: [0.5 0.5 0.5]

Example: 'blue'

Marker fill color, specified as one of these values:

  • 'none' — Use no color, which makes the interior invisible.

  • 'auto' — Use the same color specified in the MarkerEdgeColor property.

  • RGB triplet or character vector of a color name — Use the specified color.

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]. This table lists the long and short color name options and the equivalent RGB triplet values.

Long NameShort NameRGB Triplet
'yellow''y'[1 1 0]
'magenta''m'[1 0 1]
'cyan''c'[0 1 1]
'red''r'[1 0 0]
'green''g'[0 1 0]
'blue''b'[0 0 1]
'white''w'[1 1 1]
'black''k'[0 0 0]

Example: [0.3 0.2 0.1]

Example: 'green'

More About

collapse all

Tips

  • Use element-wise operators for the best performance and to avoid a warning message. For example, use x.*y instead of x*y. For more information, see Array vs. Matrix Operations.

  • When you zoom in on the chart, fimplicit recalculates the data, which can reveal hidden details.

See Also

Functions

Properties

Introduced in R2016b

Was this topic helpful?
MATLAB Documentation
Other Documentation
Support