Final Project Step 9 Error: # operator is invalid for atomic vectors

[mtwelker]

I was able to complete steps 1-8 successfully, producing the same output that is shown in the instructions. For Step 9, I copied the code you provided and pasted it in a code chunk that starts with {r, fig.height=7, fig.width=10} The only edit I made to the provided code was to change create_table to create_salary_table, since that's the name of my function:

d2 %>%  
  filter( Department.Description == "Psychology" ) %>% 
  create_salary_table( ) %>%  
  build_graph( unit="Psychology" )

When I knit, I get the following error: Error: $ operator is invalid for atomic vectors Execution halted

I looked up the error and learned that it happens if you try to access an element of a single vector with "$". For example:

> x <- c(1, 3, 7, 6, 2)
> names(x) <- c('a', 'b', 'c', 'd', 'e')
> x
a b c d e 
1 3 7 6 2 
> x$e
Error in x$e : $ operator is invalid for atomic vectors

In the example above, x is not a dataframe, so I can't access the '2' with x$e.

I have carefully looked through the code you provided for step 9, and I don't see the '$' symbol being used this way. Am I missing something? Any other ideas for why I'm getting this error?

[lecy]

It means you probably created an empty data frame at a subset or filter step. Check the data frame before the step, then walk through the pipe one step at a time to make sure you are not dropping all observations.

[mtwelker]

Thank you! That helped me identify my problem. I had used pander() inside a function, so the result was no longer a dataframe.

[ndavis4904]

I am having a problem with the same step. I made similar changes, but have an error message "Error in build_graph(., iq_range, unit = "Psychology"): Unused argument (iq_range). iq_range is what I used in the last step as the name for the dataframe that would be created with create_salary_table(). Is this because of an empty dataframe as well? Or something different entirely?

[lecy]

@ndavis4904 can you share the code that produced that error? It’s hard to tell without seeing what you are running.

[ndavis4904]

`add_position <- function( t, position, y, xmax, scale.f=8 ) {

t.original <- t t <- filter( t.original, titles==position ) dot.size <- 2 + scale.fsum(t$p) offset.n <- 1 + sum(t$p)2

male.median <- NA n.male <- NA t <- filter( t.original, titles==position & gender == "male" ) if( nrow(t) > 0 ) { male.median <- t$q50 n.male <- t$n }

female.median <- NA n.female <- NA t <- filter( t.original, titles==position & gender == "female" ) if( nrow(t) > 0 ) { female.median <- t$q50 n.female <- t$n }

dumbell plots

segments( x0=female.median, x1=male.median, y0=y, col=gray(0.3,0.5), lwd=7 ) points( male.median, y, col=adjustcolor( "darkblue", alpha.f = 0.5), pch=19, cex=dot.size ) points( female.median, y, col=adjustcolor( "firebrick", alpha.f = 0.5), pch=19, cex=dot.size )

pos.f <- 2 pos.m <- 4 if( ! ( is.na(female.median) | is.na(male.median) ) ) { pos.f <- ifelse( female.median > male.median, 4, 2 ) pos.m <- ifelse( female.median > male.median, 2, 4 ) }

add salaries to right and left

text( female.median, y, paste0("$",round(female.median/1000,0),"k"), col=adjustcolor( "firebrick", alpha.f = 0.7), cex=1.2, pos=pos.f, offset=offset.n ) text( male.median, y, paste0("$",round(male.median/1000,0),"k"), col=adjustcolor( "darkblue", alpha.f = 0.7), cex=1.2, pos=pos.m, offset=offset.n )

add faculty counts

n.female <- ifelse( is.na(n.female), 0, n.female ) n.female <- ifelse( nchar(n.female)==1, paste0( " ", n.female), n.female ) n.male <- ifelse( is.na(n.male), 0, n.male ) n.male <- ifelse( nchar(n.male)==1, paste0( " ", n.male), n.male ) text( xmax-0.1xmax, y+0.14, paste0( "f = ", n.female), col="gray50", cex=1.1, pos=4 ) text( xmax-0.1xmax, y-0.14, paste0( "m = ", n.male), col="gray50", cex=1.1, pos=4 )

axis( side=2, at=y, labels=position, las=2, tick=F, cex.axis=1.5, col.axis="gray50" ) }

build_graph <- function( t.salary, unit ) { unique.titles <- unique( t.salary$titles ) ymax <- length(unique.titles) xmax <- round( max(t.salary$q50), -3 ) + 50000 color.key.pos <- 40000 + ( xmax - 40000 ) / 2 color.key.inc <- ( xmax - 40000 ) / 10

t.mf <- filter( t.salary, gender %in% c("male","female") ) N <- sum( t.mf$n )

par( mar=c(6,15,4.1,0) ) plot.new() plot.window( xlim=c(40000-10000,xmax), ylim=c(0,ymax+1) )

abline( v=seq(40000,xmax-40000,20000), lwd=1.5, lty=2, col=gray(0.5,0.5) ) axis( side=1, at=seq(40000,xmax-40000,20000), labels=paste0("$",seq(40,(xmax-40000)/1000,20),"k"), cex.axis=1.1, col.axis="gray40", tick=FALSE )

y <- ymax

if( "Full Professor" %in% unique.titles ) { add_position( t.salary, position="Full Professor", y, xmax ) y <- y-1 } if( "Associate Professor" %in% unique.titles ) { add_position( t.salary, position="Associate Professor", y, xmax ) y <- y-1 } if( "Assistant Professor" %in% unique.titles ) { add_position( t.salary, position="Assistant Professor", y, xmax ) y <- y-1 } if( "Teaching Faculty" %in% unique.titles ) { add_position( t.salary, position="Teaching Faculty", y, xmax ) y <- y-1 } if( "Researcher" %in% unique.titles ) { add_position( t.salary, position="Researcher", y, xmax ) y <- y-1 }

text( color.key.pos + 3color.key.inc, 0, "MALE", col=adjustcolor( "darkblue", alpha.f = 0.7), cex=1.2 ) text( color.key.pos + 1.8color.key.inc, 0, "FEMALE", col="firebrick", cex=1.2 ) text( xmax - 0.1*xmax, 0, paste0("N = ",N), col="gray40", cex=1.2, pos=4 )

title( main="Median Salary by Rank and Gender", cex.main=1.5, col.main="gray30" ) title( xlab=unit, col.lab="gray50", cex.lab=1.5, line=5 ) title( xlab="dot size represents proportion of faculty at that rank", col.lab="gray50", cex.lab=0.9 )

return(NULL) }

d2 %>%
filter( Department.Description == "Psychology" ) %>% create_salary_table( ) %>% build_graph(iq_range, unit="Psychology" )`

iq_range is what I used instead of your t.salary from the previous step. Then the error is: Error in build_graph(., iq_range, unit = "Psychology") : unused argument (iq_range) calls: ... withCallingHandlers -> withvisible -> eval -> eval -> %>%

[lecy]

The build graph function is expecting a specific type of table:

build_graph <- function( t.salary, unit )

If you use a different type of data frame or object the function won’t be able to find the info it needs to build the graph.

What is iq_range here?

[ndavis4904]

That's the dataframe that we created with the create_salary_table() function.

[lecy]

If you just remove iq range does this work then?

d2 %>%
filter( Department.Description == "Psychology" ) %>%
create_salary_table( ) %>%
build_graph(iq_range, unit="Psychology" )

[lecy]

That's the dataframe that we created with the create_salary_table() function.

Since you are piping results the data frame will be passed forward from the previous step and is the implied first argument:

d %>%
  create_salary_table( ) %>%
  build_graph( [INVISIBLE DF], unit="Psychology" )

[ndavis4904]

It creates a graph, there's just no data within the graph.

[lecy]

It’s probably an issue with the table step then:

d %>%
  create_salary_table( )

[ndavis4904]

It gives me a message that says summarise() has grouped output by 'titles'. You can override using the .groups argument. Would that be the cause? In which case it would be in my function that I would need to look.

[lecy]

Did you use this code?

https://watts-college.github.io/cpp-527-fall-2021/labs/final-project-instructions.html#step-8-summarize-salaries

[ndavis4904]

Yes I did. That's the code that I put into the create_salary_table() function.

[lecy]

Including pander()?

[ndavis4904]

Originally it was outside of the function. I just changed it, and it fixed the sorting message in step 8, but I still have the same problem in step 9.

[lecy]

You don’t want to include it inside the function. It converts the table into text, so you would not be able to use it in subsequent steps.

See if you can get that table working before trying Step 9

[ndavis4904]

Is the 'title' variable supposed to be the list of code_titles() from an earlier step? It is still saying that it is grouping by titles, but other than that it gives a table with the quartiles.

[lecy]

Correct. Also helpful if you share the return table.

If the table works the graphing function should work. I would need to see output to assess though.

[ndavis4904]

I set up a time to meet with you during office hours tomorrow.