Posts Tagged ‘1-line’
Read int from stdin all in just 1 Line (Java 6 or higher)
int n = Integer.parseInt(System.console().readLine());
R: Annotate the panels in a multi-panel lattice plot in 1 line
Just use panel.lmline()
Rails: Add data from seeds to db in 1 Line
rake db:seed
Quick Tip: Run JavaScript Code Block if an Element has been Clicked (in 1 Line)
.click(function(){CODE TO RUN GOES HERE})
Ten 1-line R Hacks to Boost your Productivity
Here are 10 1-line R hacks that will streamline your workflow and increase your productivity.
1. Install problematic packages from source (solves 99% of installation problems)
install.packages(file_name_and_path, repos = NULL, type="source")
The Bash/shell equivalent would be:
R CMD INSTALL source.library
2. Count number of unique rows with a condition
length(unique(df$col[df$col > 0]))
3. Force R not to use scientific notation
options("scipen"=100, "digits"=4)
4. Count number of non-unique, non-NA rows with a condition
sum(data$x<0, na.rm=T)
5. Randomly order rows (useful for drawing a random sample)
sample(1:nrow(df))
6. Conduct pattern matching with wildcards (no REGEX required)
glob2rx("blue*")[1] "^blue"
7. Add a column of row numbers to a dataframe/object
df$row <- 1:nrow(df)
8. Loop through each unique date and build a subset
uniq <- unique(unlist(data$Date)); for (i in 1:length(uniq)){ data_1 <- subset(data, date == uniq[i]) #your desired function}
9. Drop columns by name
treatment.data <- treatment.data[, !names(treatment.data) %in% c(“name”, “name1”, “name2”)]
10. Append something to column names
names(df) <- str_c(nam, '.yourstring’)
Quick Tip: Create Table as Select (CTaS) Hack in MS SQL Server in 1 Line
select * into target_table from [DB]. [dbo].[table]
Quick Tip: Get the Size of MS SQL Server Table in 1 Line
sp_spaceused ‘[dbo].[table]’
Quick Tip: Show Postgres/pSQL Tables in Postgres OR R in 1 Line
Outside of R:
\dt
In R:
dt <- dbGetQuery(con1, “SELECT * FROM pg_catalog.pg_tables”)