Psych toolbox Screen('DrawDots' or ScreenDrawDots function

[mst]

Hello Psych Toolbox users,
I am a new user to this toolbox.

I want to use the Screen command to draw dots, but I get an error. Could anyone help me what I am doing wrong? Syntax and error are below.

I tried using either of the commands:
ScreenDrawDots(windowPtr, xy [,dotdiameter=1] [,dotcolor=white] [,center2D] [,dot_type=1]);

Screen('DrawDots', window, xy [,dotdiameter=1][,dotcolor=white][,center2D][,dot_type=1]);

The error I get:
Error: Unbalanced or unexpected parenthesis or bracket.
It is showing the arrow at the left parenthesis for this: [,dotdiameter

The syntax that is in the toolbox comes up as below:
Usage:

[minSmoothPointSize, maxSmoothPointSize, minAliasedPointSize, maxAliasedPointSize] =
Screen('DrawDots', windowPtr, xy [,size] [,color] [,center] [,dot_type][, lenient]);

What am I missing?

Thanks.
- Anita

[Jeff]

On Thursday, March 22, 2018 at 10:37:09 AM UTC+13, mst wrote:

> I tried using either of the commands:
> ScreenDrawDots(windowPtr, xy [,dotdiameter=1] [,dotcolor=white] [,center2D] [,dot_type=1]);

Try removing the square brackets from your commands. In this notation:

> [minSmoothPointSize, maxSmoothPointSize, minAliasedPointSize, maxAliasedPointSize] =
> Screen('DrawDots', windowPtr, xy [,size] [,color] [,center] [,dot_type][, lenient]);

the square brackets are just used to indicate that the parameters are optional.
You aren't actually supposed to include those brackets when calling the function.

You might also check out:
https://groups.yahoo.com/neo/groups/psychtoolbox/conversations/topics
which is more focused on the toolbox than this newsgroup.