How to return column value of that string value when given as input

Question

I have a below data frame for which I must search the string values and return the other columns It should return values depending on the input I give

Ex : 
Enter the number you want to search
Input 1 = 14
Inout 2 = 16

Combining above two, I have 14,16 as a string, then it should return me the below

rhs        name 
15          salt

Below is the Dataframe where we can search our inputs(it should search only on lhs )

DF:

lhs         rhs              name
32,39,6     65          jackfruit
39,6,65     32          coffee
14,16,26    15         salts
16,20,4     26           marshmallows
16,26,33    4            veggies
53          31           candy

This search should accept for any number of strings and should be able to search. For suppose, my input is 14,16,26 it should return the value

rhs name
15  salt

Also, if its only 16, then it should return

Rhs      name
15        salts 
26        marshmallows 
4           veggies.

I have tried using the below code but it just uses the order for example:

CODE:

df[grep('16,20', df$lhs),]

output :

rhs   name
    26    marshmallows

But if change my search like below,

CODE:

df[grep('16,4', df$lhs),] (#leaving the number 20 )

the above one gives me an error.

Expected output :

 rhs   name
    26    marshmallows

[How to make a great R reproducible example?](http://stackoverflow.com/questions/5963269) — Sotos, May 11 '18 at 09:20
Don't work with CSV data like this. Instead, get your range spread out over rows and columns. — Tim Biegeleisen, May 11 '18 at 09:21
What I'm saying is that if you model the range as a starting and ending value, each in its own column, it will probably be easier to work with than a CSV list. — Tim Biegeleisen, May 11 '18 at 09:52
@Sotos Can you help me out now, I think you should be having an idea now. — pylearner, May 11 '18 at 10:27

Tino · Accepted Answer · 2018-05-11T11:58:33.963

1

You can try that:

df <- read.table(text = "lhs         rhs              name
32,39,6     65          jackfruit
39,6,65     32          coffee
14,16,26    15         salts
16,20,4     26           marshmallows
16,26,33    4            veggies
53          31           candy    ", header = T, stringsAsFactors = F)

# define input values:
input1 <- 14
input2 <- 16

library(dplyr)

# create a data frame in long format for search:
search_df <- unnest(mutate(df, lhs = strsplit(x = lhs, split = "\\D+")))

# now search for names where all inputs are in lhs:
search_df %>% 
  group_by(name) %>% 
  filter(all(c(input1, input2) %in% lhs)) %>% 
  ungroup() %>% 
  distinct(rhs, name)

Edit: If you want more flexibility regarding inputs, just go for one:

input <- c(14, 16)
search_df %>% 
  group_by(name) %>% 
  filter(all(input %in% lhs)) %>% 
  ungroup() %>% 
  distinct(rhs, name)

edited May 11 '18 at 11:58

answered May 11 '18 at 10:50

Tino

2,091
13
15

what if I dont enter any value for `input 2` ? and my `input 1` is still 14, it should return me the one which contains only 14 ...can we get that ? – pylearner May 11 '18 at 10:58
@pylearner maybe it is better to use just one input but give it more than one value, for example `input <- c(14)` or `input <- c(14, 16)` . Otherwise, just set `input2 <- NULL`. But my advise would be to go for the single-input-approach. – Tino May 11 '18 at 11:56
Thanks Tino, Also look at my solution .. :) – pylearner May 13 '18 at 18:29

score 0 · Answer 2 · answered May 13 '18 at 18:30

0

library(rje)
myfun <- function(input){
    result <- apply(rules, 1, function(x){is.subset(input, as.vector(unlist(strsplit(x[2], ','))))})
    result <- rules[result, ]

    return (result)
}

answered May 13 '18 at 18:30

pylearner

1,358
2
10
26

How to return column value of that string value when given as input

2 Answers2