Help with filter and select function

Hi, and welcome to community.rstudio.com! Without knowing what your data and code look like, it's a little hard to answer your question. To help you get the right help for your question, can you please turn it into a reprex (reproducible example)? This will ensure we're all looking at the same data and code. A guide for creating a reprex can be found here.

From a high level, filter() and select() are different verbs in the tidyverse. filter() operates on rows, whereas select() operates on columns.

For example, in the reprex below, I'm using the built-in mtcars dataset to illustrate using filter() to retain certain rows by a certain criterion of interest, or using select() to retain certain columns based on column names.

library(tidyverse)

str(mtcars)
#> 'data.frame':    32 obs. of  11 variables:
#>  $ mpg : num  21 21 22.8 21.4 18.7 18.1 14.3 24.4 22.8 19.2 ...
#>  $ cyl : num  6 6 4 6 8 6 8 4 4 6 ...
#>  $ disp: num  160 160 108 258 360 ...
#>  $ hp  : num  110 110 93 110 175 105 245 62 95 123 ...
#>  $ drat: num  3.9 3.9 3.85 3.08 3.15 2.76 3.21 3.69 3.92 3.92 ...
#>  $ wt  : num  2.62 2.88 2.32 3.21 3.44 ...
#>  $ qsec: num  16.5 17 18.6 19.4 17 ...
#>  $ vs  : num  0 0 1 1 0 1 0 1 1 1 ...
#>  $ am  : num  1 1 1 0 0 0 0 0 0 0 ...
#>  $ gear: num  4 4 4 3 3 3 3 4 4 4 ...
#>  $ carb: num  4 4 1 1 2 1 4 2 2 4 ...

# Filtering for cars with 6 cylinders

cars_6cyl <- mtcars %>% filter(cyl == 6) %>% head()
cars_6cyl
#>    mpg cyl  disp  hp drat    wt  qsec vs am gear carb
#> 1 21.0   6 160.0 110 3.90 2.620 16.46  0  1    4    4
#> 2 21.0   6 160.0 110 3.90 2.875 17.02  0  1    4    4
#> 3 21.4   6 258.0 110 3.08 3.215 19.44  1  0    3    1
#> 4 18.1   6 225.0 105 2.76 3.460 20.22  1  0    3    1
#> 5 19.2   6 167.6 123 3.92 3.440 18.30  1  0    4    4
#> 6 17.8   6 167.6 123 3.92 3.440 18.90  1  0    4    4

# Subsetting to a few columns of interest (mpg, cyl, and disp)

cars_subset <- mtcars %>% select(mpg, cyl, disp) %>% head()
cars_subset
#>                    mpg cyl disp
#> Mazda RX4         21.0   6  160
#> Mazda RX4 Wag     21.0   6  160
#> Datsun 710        22.8   4  108
#> Hornet 4 Drive    21.4   6  258
#> Hornet Sportabout 18.7   8  360
#> Valiant           18.1   6  225

Created on 2018-10-06 by the reprex package (v0.2.0).

I hope this helps! If not, can you please add a minimal reprex with your data and code?

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