Technical drawing | Statistical charts and diagrams | Non-Newtonian calculus
Semi-log plot
In science and engineering, a semi-log plot/graph or semi-logarithmic plot/graph has one axis on a logarithmic scale, the other on a linear scale. It is useful for data with exponential relationships, where one variable covers a large range of values, or to zoom in and visualize that - what seems to be a straight line in the beginning - is in fact the slow start of a logarithmic curve that is about to spike and changes are much bigger than thought initially. All equations of the form form straight lines when plotted semi-logarithmically, since taking logs of both sides gives This is a line with slope and vertical intercept. The logarithmic scale is usually labeled in base 10; occasionally in base 2: A log–linear (sometimes log–lin) plot has the logarithmic scale on the y-axis, and a linear scale on the x-axis; a linear-log (sometimes lin–log) is the opposite. The naming is output-input (y-x), the opposite order from (x, y). On a semi-log plot the spacing of the scale on the y-axis (or x-axis) is proportional to the logarithm of the number, not the number itself. It is equivalent to converting the y values (or x values) to their log, and plotting the data on linear scales. A log–log plot uses the logarithmic scale for both axes, and hence is not a semi-log plot. (Wikipedia).
