Frequently Asked Questions

Here are the answers to some common questions about SasView:

What is SasView?

What platforms does SasView run on?

Do I need to install Python/C++ before I install SasView?

Can SasView make use of my GPU(s)?

Can I stop SasView trying to use my GPU(s)?

Can I use SasView to analyse SANS/USANS data?

Can I use SasView to analyse SAXS/USAXS data?

Can SasView be used in a commercial environment?

What format should my data be in?

What units should my data be in?

Does SasView fit data in its I vs Q representation, or as Log I vs Log Q?

Many models have a scale parameter; what is this?

How can I put my data on an absolute intensity scale?

Why do I get non-sensical parameter values if I try to simultaneously model-fit the scale factor and the scattering length densities?

What value should I use to specify polydispersity?

Is the Schulz(-Zimm) polydispersity function used in SasView a number-average or a weight-average distribution?

What about the other polydispersity functions used in SasView?

How do I load an image file as data?

Where do the model parameter uncertainties come from?

Why do I get different parameter uncertainties using the Simple and Complex fitting engines?

Why do I sometimes get different 'goodness-of-fit' values when pressing Enter or Compute compared to pressing Fit?

Why is SasView not loading the model parameters from some of my existing .fitv (Save Fit) files?

Why is Save Analysis (File menu) greyed out after I fit a model?

Why doesn't Check for Updates work?

Why is SasView no longer able to run my existing custom models?

How can I see the separate contributions of the form factor and structure factor?

How can I include a structure factor in a model?

What is the Model Marketplace?