This help page is intended to provide users with a source of information concerning any issues that may arise during the use of the application. This is by no means exhaustive, so if there is an issue that you are having which is not mentioned here, please get in touch with us and we will endeavour to answer your questions.
Error message: “Compile error: Can’t find project or library”.
This error has been found on computers running Microsoft Office Excel 2007. The error is caused when the Microsoft Visual Basic compiler is unable to locate the Solver reference file.
Solver is not automatically loaded when Excel is installed. The first time Solver is invoked you will get a message saying that it cannot be run but will ask if you want to install it. You will likely need the installation disks during the install.
Advanced User Tips
If you have independent information about mesophyll conductance or day respiration, enter the value in the output region, then invoke Solver from the tools menu and adjust it so that the values you entered are not changed during fitting of the model.
If you want to explore, for example, how photosynthesis would change if rubisco were genetically engineered to go twice as fast, change the Vcmax and observe the effect on the lines. The data to draw the lines are at the bottom of the Calculations page.
It didn't work!
If Solver is unable to find a solution no changes will be made and the lines will not fit. Try adjusting the values manually to get an approximate fit and then try the "Solve" button again. Sometimes this allows Solver to find a realistic solution.
It still didn't work!
Estmate gm as 0.1 times A at 25 Pa and Rd as 1. Then, using solver as described in Advanced use tips estimate Vcmax, J, and TPU (do not allow gm and Rd to be changed by solver). This allows you to get some information out of the data. Use other estimates for gm and Rd if you have information about these.
If there are any issues that are not covered, please feel free to contact us to discuss further at firstname.lastname@example.org.