I think this should do the thing for you:
str <- " -26755.22-50150.60"
#you can use this command to split the data into 2 columns
#this doesn't have any constraint in the number of digits before and after the decimal
strspl <- as.numeric(unlist(regmatches(str,gregexpr("(?>-)*[[:digit:]]+\\.*[[:digit:]]*",str, perl=TRUE))))
 -26755.22 -50150.60
If you want to store the outcome in a data-frame then you can use the below command
#everything is same but instead of as.numeric we replace it with as.data.frame
str_df <- as.data.frame(unlist(regmatches(str,gregexpr("(?>-)*[[:digit:]]+\\.*[[:digit:]]*",str, perl=TRUE))))
#it is not necessary to change the column but it is a good practice to do so
colnames(str_df) <- "variable_1"
Let me know if you have any doubt, would help you.
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