what is lw within the semilogx function in matlab

lw within the semilogx function in MATLAB stands for "line width". It specifies the width of the line used to plot the data on the semilogarithmic scale. The lw option is used in conjunction with the semilogx function in the following way to set the line width to, for example, 2:

main.m
semilogx(x,y,'LineWidth',2)
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This will plot the data specified by x and y on a semilogarithmic scale using a line with width 2. The larger the line width, the more visible the data will be when plotted.