A variable can hold quantities or values in memory that can be referenced using a variable name. You can store values in a variable to use in your experiments.
Everything in a PsychoPy® experiment needs a unique name. The name should contain only letters, numbers and underscores (no punctuation marks or spaces). The variable name references the value stored in memory, so that your stored values can be used in your experiments.
The time or condition from when you want your variable to be defined. The default value is None, and so will be defined at the beginning of the experiment, trial or frame. See Defining the onset/duration of components for details.
The duration for which the variable is defined/updated. See Defining the onset/duration of components for details.
The variable can take any value at the beginning of the experiment, so long as you define you variables using literals or existing variables.
The variable can take any value at the beginning of a routine/trial, and can remain a constant, or be defined/updated on every routine.
The variable can take any value at the beginning of a frame, or during a condition bases on Start and/or Stop.
What information to save, how to lay it out and when to save it.
Choose whether or not to save the experiment start value to your data file.
Choose whether or not to save the routine start value to your data file.
Frame values are contained within a list for each trial, and discarded at the end of each trial. Choose whether or not to take the first, last or average variable values from the frame container, and save to your data file.
Choose whether or not to save the routine end value to your data file.
Choose whether or not to save the experiment end value to your data file.