renjin

Renjin could not find function 'engine.eval

I am running Java on Linux (CentOS), via the command line.

When I put the R command is a separate file, described in Section 1.4 of these docs,

I get the error:

Exception in thread "main" org.renjin.eval.EvalException: could not
find function 'engine.eval'
    at org.renjin.eval.Context.evaluateFunction(Context.java:269)
    at org.renjin.eval.Context.evaluateCall(Context.java:260)
    at org.renjin.eval.Context.evaluate(Context.java:193)
    at org.renjin.eval.Context.evaluateExpressionVector(Context.java:252)
    at org.renjin.eval.Context.evaluate(Context.java:191)
    at org.renjin.script.RenjinScriptEngine.eval(RenjinScriptEngine.java:131)
    at org.renjin.script.RenjinScriptEngine.eval(RenjinScriptEngine.java:127)
    at org.renjin.script.RenjinScriptEngine.eval(RenjinScriptEngine.java:107)
    at pkg3.Temp3.main(Temp3.java:31)

I have the CLASSPATH set correctly, because:

cd ~/rjtest
javac pkg3/Temp3.java

cd ~/rjtest
java pkg3.Temp3

produces:

   x      y
 1  1      1.121
 2  2      0.525
 3  3      1.811
 4  4      1.914
 5  5      5.389
 6  6      8.501
 7  7      6.477
 8  8      7.805
 9  9      8.625
10 10     10.033

Call:
lm(formula = y ~ x, data = df)

Coefficients:
(Intercept) x
-0.902       1.113

Modifing the code to move the 3 engine.eval statements into script.R:

// engine.eval("df <- data.frame(x=1:10, y=(1:10)+rnorm(n=10))");
// engine.eval("print(df)");
// engine.eval("print(lm(y ~ x, df))");

engine.eval(new java.io.FileReader("/pathto/rjtest/pkg3/script.R"));

javac compiles with no error, but java gives the error.

Solution

  • The code engine.eval() is a Java statement. The Exception you're getting is Renjin telling you that there is no R function called engine.eval. Your script.R should contain:

    df <- data.frame(x=1:10, y=(1:10)+rnorm(n=10))
print(df)
print(lm(y ~ x, df))"

    Not:

    engine.eval("df <- data.frame(x=1:10, y=(1:10)+rnorm(n=10))")
engine.eval("print(df)");
engine.eval("print(lm(y ~ x, df))")

    Which is, coincidentally, valid R syntax, but not what you want.