mt_remap_symmetric() Error in if ((remap_ypos == "up" & trajectories[i, nlogs, ypos] < 0) | :

Comments

• alexamb

  October 2022 edited October 2022

  I should mention that I am using data from EPrime. We take the .txt file and export it as a .csv file so that I can read it in R. The only difference with my mousetrap preprocessing steps is that we have to align our data first and then remap. I believe it has something to do with the way the mouse-tracking experiment is setup in EPrime. I can confirm that those steps work as I've already produced results/plots. I'm just have issues with this particular subject.. I think it has to do with how inconsistent their trajectories are, but I don't know how to handle that issue. Thanks!
• Pascal

  November 2022

  Hi,

  that's an interesting error and without knowing more about the data it is a bit hard to uncover the source.

  I took a look at the code of mt_remap_symmetric again (I assume that this is the remapping function you are using): The error specifically seems to occur because the last checked y position is a missing value (NA) (see code here: https://github.com/PascalKieslich/mousetrap/blob/master/R/preprocess.R#L218). This might happen because the number of logged y coordinates is less than the number of logged x coordinates (inernally, the function uses the number of x coordinates to determine the last position in a specific trial).

  In practice, this should never happen, but you could check whether this is the case in your data by running:

  # Number of logged x coordinates
  n_logged_x_pos <- mt_count(mt_example$trajectories, dimensions="xpos")
  
  # Number of logged y coordinates
  n_logged_y_pos <- mt_count(mt_example$trajectories, dimensions="ypos")
  
  # Check whether number of logged coordinates is always the same (all should be TRUE)
  table(n_logged_x_pos==n_logged_y_pos)
  

  Best,

  Pascal
• alexamb

  November 2022

  Hi Pascal,

  
  

  Thanks so much for responding! This definitely helps because after looking through the data more, I was able to find that for some subjects, all the data didn't export leaving some missing values for the logged coordinates (as you mentioned is the case).