# Semi Log Graph

In the field of science and engineering, a semi log graph has one axis on a logarithmic scale, while the other is on a linear scale. The semi log graph paper is useful for data that has exponential relationships, while one variable covers a large range of values, or to zoom in and visualize what seems to be a straight line at the start is in fact the slow beginning of a logarithmic curve that is almost going to spike and changes are much bigger than thought initially. A log linear graph has the logarithmic scale on the y-axis, while having a linear scale on the x-axis. A linear log graph is the opposite of a log linear graph as the name suggests. The naming is output-input (y-x). On a semi log graph paper, the spacing of the scale on the y axis is proportional to the logarithm of the number and not the number itself. It is like converting the y values to their logarithmic equivalents, and plotting the data on linear scales. A log log graph uses the logarithmic scale for both axes, and hence is not a semi log graph.

There are several uses for semi log graphs, a few of which are given below:

• In the field of physics and chemistry, a plot of logarithm against temperature can be used to show the different phases of a substance
• While ten is the most common base, other bases are also used when appropriate, like in the case of graphs that show flu breakout curves