I am trying to count how many 'S' appears in each column as 'downstream' from 1 to 10 rows and then as 'upstream' from 15 to 25.

Then I want to save the output in a text file.
Well, I managed to work out for a single example. Unfortunately, I have a problem with a loop through the columns to be saved as well. In this case, the number of columns is 5 but that can vary depending on the file.

```
#data frame
S <- data.frame(scale = c(0, 0, 0, 0, 0, 0 , 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0), 
                aa = c('A','C','D','E','F','G','H','I','K','L','M','N','P','Q','R','S','T','V','W','Y'))

    #input  (example)
   V1  V2  V3  V4  V5 
1  C   D   E    R   N  
2  C   A   M    K   P
3  V   T   Q    Q   E 
4  A   T   S    S   S
5  C   D   E    R   N  
6  C   A   M    K   P
7  V   T   Q    Q   E 
8  A   T   S    S   S
9  R   V   D    S   A
10 W   R   H    I   C
11 S   N   I    P   T
12 Q   A   S    D   E
13 C   D   E    R   N  
14 C   A   M    K   P
15 V   T   Q    Q   E 
16 A   T   S    S   S
17 C   D   E    R   N  
18 C   A   M    K   P
19 V   T   Q    Q   E 
20 A   T   S    S   S
21 R   V   D    S   A
22 W   R   H    I   C
23 S   N   I    P   T
24 G   A   D    S   S 
25 N   T   T    S   A

# matching the data from two data frames
  df11 <- df_trial %>%
  pivot_longer(cols = everything(), values_to = 'aa') %>%
  mutate(aa = replace(aa, aa == '-', '')) %>%
  left_join(S, by = 'aa') %>%
  arrange(name) %>%  
  group_by(name) %>% 
  mutate(row = row_number())  
  view(df11)

  values_for_all <- df11 %>%
  pivot_wider(names_from = name, values_from = c(scale, aa)) %>% 
  select(-row) 
  view(values_for_all)
 #class(values_for_all)

```

#problem with loop through the columns here:!!!!!!!!!!!!!!!!!

```
 #sum values from positions 1 to 10 and then from  15 to 25
    downstream <- sum(values_for_all$scale_V1[1:11])
    #view(downstream)
    upstream <- sum(values_for_all$scale_V1[15:25])
    #view(upstream)

res <- cbind(downstream,upstream) 
res_trial<- as.data.frame(t(res))
view(res_trial)
#class(res_trial)
#converting a matrix to the data frame
res_final <- as.data.frame(t(res_trial))
view(res_final)
#class(res_final)

#saving to a text file
write.table(res_final,"~/Desktop/R_work/test.txt",sep="\t",row.names=FALSE)

#expected outcome (example):

downstream   upstream
   2            0
   0            0

```

Thank you for your help!