Multiplying a function by a constant looks like adding a constant offset on a log-log plot.Power laws are linear on a log scale, with a slope equal to their exponent.Log plots are useful when you want to emphasize the limiting behavior of functions, or compare several functions over a large range of values.Although they can be counterintuitive at first, with practice they will actually become useful tools in your data visualization arsenal. If you'd like more practice I would recommend firing up MATLAB and plotting a variety of functions on both log and linear scales. Hopefully this page has refreshed your memory on logarithms and log scales. The goal of this page is to help you get familiar enough with log plots so that you can easily interpret and sketch functions on a log scale. In the above figure, you can see only the y-axis is in the log scale of base 10.Log plots pop up in 20.309 surprisingly frequently. a = 1:100 b = 2*a lg = semilogy(a,b) grid on axis tight Make a two-dimensional plot using a log scale for the y axis. If you want to plot the variables on the y-axis of base 10 log scale and x-axis of linear scale. If you are familiar with Matlab plot syntax, you should use plot. Log Plot Using the semilogy() Function in MATLAB You can also add legends to the plot using the legend() function. You can also plot multiple variables and matrices with different line styles, markers, and colors to make them different from one another using the same method described in the loglog() function. In the above figure, only the x-axis is in the log scale of base 10. a = 1:100 b = 2*a lg = semilogx(a,b) grid on axis tight If you want to plot the variables on the x-axis of base 10 log scale and y-axis of linear scale. Log Plot Using the semilogx() Function in MATLAB As you can see in the figure, there are 10 lines, one for each column. In the above code, we have plotted a matrix containing 10 columns. a = 1:10 b = 2*a c = 3*a mat = lg = loglog(mat) grid on axis tight In the matrix case, each column will be plotted as a different variable with a different color on the same figure. You can also plot a matrix using the loglog() function. You can also add legends on the plot using the function to mention which plot belongs to which variable. For example, let’s plot another variable on the above figure with different colors and markers. You can also plot multiple variables on the same figure.

You can also change other properties like marker size, marker edge color, marker face color in the loglog() function. In the above code, we plot a variable on a log scale of base 10 with a line width of 3, a circle marker, and black color. a = logspace(0,10) b = 3.^a loglog(a,b,'-ok','LineWidth',3) grid on axis tight For example, let’s plot the above variable again with different properties. You can also change the plot using different line styles, markers, and colors. In the above figure, you can see both the axis are in the log scale of base 10. a = logspace(0,10) b = 3.^a loglog(a,b) grid on If you want to plot the variables on a base 10 logarithmic scale on the x-axis and y-axis, you can use the function. Log Plot Using the loglog() Function in MATLAB In this tutorial, we will discuss how we can plot variables on a log scale using the loglog(), semilogx(), and semilogy() functions in MATLAB.

Matlab log plot