# matlab plot log scale

Introduction to Log Plot Matlab. The freqz(z,p) gives the plot of magnitude in dB (log scale) versus the normalized frequency. 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. The scale is very useful when displaying the data over many order. Sign in to comment. 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. I am wondering how to plot in MATLAB with a logarithmic scale. These are my data. digital filter freqz plot. 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. Based on your location, we recommend that you select: . plot( log10(x), log10(y)) Alternatively, you can use the loglog command to make a plot with log-scale axes: loglog( x, … Without the logarithmic scale, the data that we plotted would show a curve with an exponential rise. Select a Web Site. MATLAB: Linear Scale of a Frequency Response Plot (freqz) – Digital Filter. Logarithms can be written as the inverse of an exponential equation. Show Hide all comments. The most common base of any logarithmic equation is always considered to be 10 if it is not specified. x = [1 0.1 0.01 0.001] y = [10 60 120 180] I want to plot x-axis in logarithmic scale. Mar 18, 2019 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. Problem is when I can have one or the other, y=-3 and my function or I can have an x axis log scale. 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. Can anyone help me please to do this? Sign in to comment. The first is to use the plot command to plot log(y) vs. log(x) on a linear scale. 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. 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. Similarly, you can apply the same for x-axis by using pyplot.xscale(‘log’). without embedded MATLAB functions. There are two ways to make a log-log plot in MATLAB. 0 Comments. These are my data. That’s all that needs to be done to plot a graph with a logarithmic scale. This term refers to the fact that the plot is logarithmically scaled in both axes. Choose a web site to get translated content where available and see local events and offers. Log Plots are the two-dimensional graphs that have a logarithmic scale in both horizontal and vertical axes. 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. Sign in to answer this question. However, I would like to have linear scale (0-1 for the y-axis), is it doable? Show Hide all comments. Can anyone help me please to do this? The log of negative real values is equal to the log of the positive value, plus (pi*1i) -- that is the result is complex. Sign in to answer this question. If yes, please assist me how to do it. 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