How do i plot a semi log graph for OD vs. time? The values for OD are under 1
adjust ur scale and use E-ve
numbers
try using ln instead of logs
dont be afriad to start ur graph later...instead of at 0 or 1
There are semi-log graph papers that you can use.
The time scale is probably linear, and the diameter is in log scale (or the other way round).
The log scales are in cycles of 10, in your case, would be 0.001 to 0.01, 0.01 to 0.1, 0.1 to 1, etc.
If you don't have semi-log graph paper, then you can take log and plot the value of log. The cycles can be adjusted accordingly.
See, for example:
http://course1.winona.edu/sberg/307s09/Labs/documents/SemiLog_files/SemiLog_22632_image001.gif
To plot a semi-log graph for OD (Optical Density) vs. time, follow these steps:
1. Make sure you have a dataset containing time measurements and corresponding OD values.
2. Open a spreadsheet software like Microsoft Excel or Google Sheets.
3. Enter your time values in one column and OD values in another column.
4. Create a new column and calculate the logarithm (base 10) of the OD values using the LOG10 function. In Excel, you can use the formula "=LOG10(A2)" assuming your OD values start in cell A2.
5. Now you have two columns, one with the original OD values and one with the logarithmic values.
6. Select the range of cells including both columns.
7. Click on the "Insert" tab and choose "Scatter" or "XY Scatter" chart. This will create a scatter plot based on your data.
8. Right-click on one of the data points on the chart and select "Chart Type" or "Change Chart Type."
9. In the "Change Chart Type" dialog box, select the "Combo" option on the left sidebar.
10. Change the chart type for the logarithmic OD values series to "Line" (or "Smooth Line" if available). Keep the original OD values as scatter points.
11. Click "OK" to close the dialog box and you will have a semi-log graph of OD vs. time.
The x-axis will represent time, linearly spaced, and the y-axis will represent the logarithmic OD values. The scale on the y-axis will be logarithmic, allowing you to plot values under 1.
Note: If your OD values are negative or zero, logarithm values cannot be calculated as logarithms of non-positive numbers do not exist.