# matlab plot log scale

There are two ways to make a log-log plot in MATLAB. I am wondering how to plot in MATLAB with a logarithmic scale. Introduction to Log Plot Matlab. These are my data. If you use xlim([5000 8000]) the plots are superficially the same because the range of x-values is so limited the difference in scaling between the log and linear axes isn't much at all. Problem is when I can have one or the other, y=-3 and my function or I can have an x axis log scale. The log of negative real values is equal to the log of the positive value, plus (pi*1i) -- that is the result is complex. I need to plot a line at y=-3 on my graph that has two functions plotted on a log scale on the x axis. Sign in to answer this question. I am wondering how to plot in MATLAB with a logarithmic scale. Sign in to comment. However, I would like to have linear scale (0-1 for the y-axis), is it doable? Show Hide all comments. If yes, please assist me how to do it. plot( log10(x), log10(y)) Alternatively, you can use the loglog command to make a plot with log-scale axes: loglog( x, … Select a Web Site. Without the logarithmic scale, the data that we plotted would show a curve with an exponential rise. digital filter freqz plot. Sign in to comment. Logarithms can be written as the inverse of an exponential equation. [C, h1] = contourf(X, Y, Z, 'ZScale', 'Log'); clabel(C,h1); and get the picture at the bottom with labels 10, 10^5, 10^10, etc. That’s all that needs to be done to plot a graph with a logarithmic scale. The first is to use the plot command to plot log(y) vs. log(x) on a linear scale. An frequently-used method is transforming data by the formular t = sign(x)*log(abs(x)), then plot the (t,y) instead of (x,y), and modify the yTickLabel manually. x = [1 0.1 0.01 0.001] y = [10 60 120 180] I want to plot x-axis in logarithmic scale. The graph will be linear with a logarithmic y-axis. Based on your location, we recommend that you select: . MATLAB: Linear Scale of a Frequency Response Plot (freqz) – Digital Filter. The freqz(z,p) gives the plot of magnitude in dB (log scale) versus the normalized frequency. The most common base of any logarithmic equation is always considered to be 10 if it is not specified. Sign in to answer this question. These are my data. 0 Comments. I know about semilogy, semilogx and loglog functions, but I'd like to understand how to perform conversion from linear scale to logarithmic scale manually, i.e. Hey guys I'm blundering through MATLAB here, I haven't officially learnt it and my Lecturer expects me to know how to use it. Summing up, I need to do one of the following: Find a way to set the logarithmic scale programmatically and let matlab worry about the isolines. Choose a web site to get translated content where available and see local events and offers. loglog - logarithmic plot In this example we are going to demonstrate how to use the ' loglog ' function included in Matlab to produce non-linear plots. 0 Comments. Show Hide all comments. Similarly, you can apply the same for x-axis by using pyplot.xscale(‘log’). When you set YScale to log, then internally it would take the log of the negative values you have, and would found that the log is complex. x = [1 0.1 0.01 0.001] y = [10 60 120 180] I want to plot x-axis in logarithmic scale. This term refers to the fact that the plot is logarithmically scaled in both axes. Log Plots are the two-dimensional graphs that have a logarithmic scale in both horizontal and vertical axes. Can anyone help me please to do this? Can anyone help me please to do this? without embedded MATLAB functions. The scale is very useful when displaying the data over many order. Mar 18, 2019