Scala (Breeze) + Intellij: "Cannot resolve symbol *" -

i'm using breeze to sum simple linear algebra operations on dense matrices. i'm using intellij idea. here snippet of code:

import breeze.linalg._     val x1:densematrix[double] = densematrix.zeros[double](10, 5) + 1.0 val n1 : double = x1.rows.todouble val one_tall_t1  = densematrix.zeros[double](1, n1.toint) + 1.0 val mu1=one_tall_t1*x1/n1 

in last line, symbols * , / shown red color in ide. error message "cannot resolve symbol *".

but intellij builds program without errors, , runs fine.

i've been trying find out reason: since i'm new scala, i'm not sure if because of intellij, breeze, or code. in posts, people have suggested invalidate cache , restart intellij, not solve issue.

i appreciate comments or solutions!

intellij gets confused complex implicit searches used in breeze. file bugs when can minimize them , around it, it's slog. (eclipse, it's worth, isn't better.)

it typically works better if you're depending on breeze, not developing inside of it. assume you're doing though.