# matlab plot log scale

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