MATLAB Functions

Semi-logarithmic plots

semilogx(Y)
semilogx(X1,Y1,...)
semilogx(X1,Y1,LineSpec,...)
semilogx(...,'PropertyName',PropertyValue,...)
h = semilogx(...)

semilogy(...)
h = semilogy(...)

Description

semilogx and semilogy plot data as logarithmic scales for the x- and y-axis, respectively.

semilogx(Y)

creates a plot using a base 10 logarithmic scale for the x-axis and a linear scale for the y-axis. It plots the columns of Y versus their index if Y contains real numbers. semilogx(Y) is equivalent to semilogx(real(Y),imag(Y)) if Y contains complex numbers. semilogx ignores the imaginary component in all other uses of this function.

semilogx(X1,Y1,...)

plots all Xn versus Yn pairs. If only Xn or Yn is a matrix, semilogx plots the vector argument versus the rows or columns of the matrix, depending on whether the vector's row or column dimension matches the matrix.

semilogx(X1,Y1,LineSpec,...)

plots all lines defined by the Xn,Yn,LineSpec triples. LineSpec determines line style, marker symbol, and color of the plotted lines.

semilogx(...,'PropertyName',PropertyValue,...)

sets property values for all Line graphics objects created by semilogx. See the line reference page for more information.

semilogy(...)

creates a plot using a base 10 logarithmic scale for the y-axis and a linear scale for the x-axis.

h = semilogx(...) and h = semilogy(...)

return a vector of handles to Line graphics objects, one handle per Line.

Remarks

If you do not specify a color when plotting more than one line, semilogx and semilogy automatically cycle through the colors and line styles in the order specified by the current Axes ColorOrder and LineStyleOrder properties.

You can mix Xn,Yn pairs with Xn,Yn,LineSpec triples, for example,

semilogx(X1,Y1,X2,Y2,LineSpec,X3,Y3)

Examples

A simple semilogy plot is:

x = 0:.1:10;
semilogy(x,10.^x)