js-call-r

JavaScript call R function with a simple way.

Integrate JaveScript and R.
JavaScript passes JSON to R script, and get JSON from R script by js-call-r module.

Install

npm install --save js-call-r

Usage

const rscript = require('js-call-r');
 
// Sync
rscript.callSync(RScript, [Args], [Options]);
 
// Async, support Promise while callback is undefined
rscript.call(RScript, [Args], [Options]);
rscript.call(Rscript, [Args], [Options], [callback]);

Synchronous

const result = call.callSync('./test/test.R', {
    a: 1,
    b: 3
});
console.log(result.result);

Asynchronous

call.call('./test/test.R', {
    a: 1,
    b: 3
})
.then((result) => {
    console.log(result.result);
})
.catch(err => {
    console.log('err = ', err);
});
 

Or

call.call('./test/test.R', {
    a: 1,
    b: 3
}, undefined, (result) => {
    console.log(result.result);
});

Options

{
    "verboseResult": true/[false]
}

false is default.

Result

If verboseResult of Options is true, call() or callSync() will return the following object.

{
    "pid": <number>,
    "result": <return from R script>
}

If it is false, the result will only include <return from R script> part.

While any error occurs, the result will be the following object.

{
    "pid": <number>,
    "error": <error message>
}

R script template

Transcate JSON data between JavaScript and R, so input and output for R scripts have to convert to JSON format.

# json library
library('rjson')
 
# function to call
sumFunc <- function (num1, num2){
  sum(num1, num2)
}
 
# get arguments of cli
args <- commandArgs(trailingOnly = TRUE)
 
# arguments to JSON
json <- fromJSON(args)
 
# call function
ret <- sumFunc(as.numeric(json$a),as.numeric(json$b))
 
# convert return of function to list
output <- list(result = ret)
 
# output JSON
print(toJSON(output));

Example

npm test

License

No License