How to remove all rows that have a numeric in the first (or any) column

Calling something a data.frame does not make it a data.frame.

The abbreviated object shown below is a list of singletons. If it is a column in a larger object that is a data.frame, then it is a list column which is valid but can be ticklish to handle within base R but less so in the tidyverse.

For example, if I try to make a data.frame the normal way, the list gets made into multiple columns and copied to each row. Not what was expected. I think some tidyverse functionality does better.

Like this:

library(tidyverse)
temp=list("Hello", 1, 1.1, "bye")

Now making a data.frame has an odd result:

mydf=data.frame(alpha=1:4, beta=temp)
mydf

alpha beta..Hello. beta.1 beta.1.1 beta..bye.
1     1        Hello      1      1.1        bye
2     2        Hello      1      1.1        bye
3     3        Hello      1      1.1        bye
4     4        Hello      1      1.1        bye

But a tibble handles it:

mydf=tibble(alpha=1:4, beta=temp)
mydf

# A tibble: 4 x 2
alpha beta     
<int> <list>   
  1     1 <chr [1]>
  2     2 <dbl [1]>
  3     3 <dbl [1]>
  4     4 <chr [1]>

So if the data does look like this, with a list column, but access can be tricky as subsetting a list with [] returns a list and you need [[]].

I found a somehwhat odd solution like this:

mydf %>%
   filter(!map_lgl(beta, is.numeric)) -> mydf2
# A tibble: 2 x 2
alpha beta     
<int> <list>   
  1     1 <chr [1]>
  2     4 <chr [1]>

When I saved that result into mydf2, I got this.

Original:
  
  > str(mydf)
tibble [4 x 2] (S3: tbl_df/tbl/data.frame)
$ alpha: int [1:4] 1 2 3 4
$ beta :List of 4
..$ : chr "Hello"
..$ : num 1
..$ : num 1.1
..$ : chr "bye"

Output when any row with a numeric is removed:

str(mydf2)

tibble [2 x 2] (S3: tbl_df/tbl/data.frame)
$ alpha: int [1:2] 1 4
$ beta :List of 2
..$ : chr "Hello"
..$ : chr "bye"

So if you try variations on your code motivated by what I show, good luck. I am sure there are many better ways but I repeat, it can be tricky.

-----Original Message-----
From: R-help <r-help-bounces at r-project.org> On Behalf Of Jeff Newmiller
Sent: Tuesday, September 14, 2021 11:54 PM
To: Gregg Powell <g.a.powell at protonmail.com>
Cc: Gregg Powell via R-help <r-help at r-project.org>
Subject: Re: [R] How to remove all rows that have a numeric in the first (or any) column

You cannot apply vectorized operators to list columns... you have to use a map function like sapply or purrr::map_lgl to obtain a logical vector by running the function once for each list element:

sapply( VPN_Sheet1$HVA, is.numeric )

Here is the output:

str(VPN_Sheet1$HVA)

List of 2174
$ : chr "Email: fffd at fffffffffff.com"
$ : num 1
$ : chr "Eloisa Libas"
$ : chr "Percival Esquejo"
$ : chr "Louchelle Singh"
$ : num 2
$ : chr "Charisse Anne Tabarno, RN"
$ : chr "Sol Amor Mucoy"
$ : chr "Josan Moira Paler"
$ : num 3
$ : chr "Anna Katrina V. Alberto"
$ : chr "Nenita Velarde"
$ : chr "Eunice Arrances"
$ : num 4
$ : chr "Catherine Henson"
$ : chr "Maria Carla Daya"
$ : chr "Renee Ireine Alit"
$ : num 5
$ : chr "Marol Joseph Domingo - PS"
$ : chr "Kissy Andrea Arriesgado"
$ : chr "Pia B Baluyut, RN"
$ : num 6
$ : chr "Gladys Joy Tan"
$ : chr "Frances Zarzua"
$ : chr "Fairy Jane Nery"
$ : num 7
$ : chr "Gladys Tijam, RMT"
$ : chr "Sarah Jane Aramburo"
$ : chr "Eve Mendoza"
$ : num 8
$ : chr "Gloria Padolino"
$ : chr "Joyce Pearl Javier"
$ : chr "Ayza Padilla"
$ : num 9
$ : chr "Walfredson Calderon"
$ : chr "Stephanie Anne Militante"
$ : chr "Rennua Oquilan"
$ : num 10
$ : chr "Neil John Nery"
$ : chr "Maria Reyna Reyes"
$ : chr "Rowella Villegas"
$ : num 11
$ : chr "Katelyn Mendiola"
$ : chr "Maria Riza Mariano"
$ : chr "Marie Vallianne Carantes"
$ : num 12

??????? Original Message ???????

On Tuesday, September 14th, 2021 at 8:32 PM, Jeff Newmiller <jdnewmil at dcn.davis.ca.us> wrote:

An atomic column of data by design has exactly one mode, so if any 
values are non-numeric then the entire column will be non-numeric. 
What does

str(VPN_Sheet1$HVA)

tell you? It is likely either a factor or character data.

On September 14, 2021 7:01:53 PM PDT, Gregg Powell via R-help r-help at r-project.org wrote:

Stuck on this problem - How does one remove all rows in a dataframe that have a numeric in the first (or any) column?

Seems straight forward - but I'm having trouble.

I've attempted to used:

VPN_Sheet1 <- VPN_Sheet1[!is.numeric(VPN_Sheet1$HVA),]

and

VPN_Sheet1 <- VPN_Sheet1[!is.integer(VPN_Sheet1$HVA),]

Neither work - Neither throw an error.

class(VPN_Sheet1$HVA) returns:

[1] "list"

So, the HVA column returns a list.

Data looks like the attached screen grab -

The ONLY rows I need to delete are the rows where there is a numeric in the HVA column.

There are some 5000+ rows in the actual data.

Would be grateful for a solution to this problem.

How to get R to detect whether the value in column 1 is a number so the rows with the number values can be deleted?

Thanks in advance to any and all willing to help on this problem.

Gregg Powell

Sierra Vista, AZ

--

Sent from my phone. Please excuse my brevity.

--
Sent from my phone. Please excuse my brevity.

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