private static void TestPendingFinalizersThreadingIssues(REngine e)
{
e.Evaluate("f <- function(a) {if (length(a)!= 1) stop('What goes on?')}");
var f = e.Evaluate("f").AsFunction();
try
{
e.Evaluate("f(letters[1:3])");
}
catch (EvaluationException)
{
}
f.Invoke(e.CreateCharacterVector(new[] { "blah" }));
try
{
f.Invoke(e.CreateCharacterVector(new[] { "blah", "blah" }));
}
catch (EvaluationException)
{
Console.WriteLine("Caught the expected exception");
}
f = null;
GC.Collect();
GC.WaitForPendingFinalizers();
e.Dispose();
Console.WriteLine("Just waiting for crash...");
GC.Collect();
GC.WaitForPendingFinalizers();
}
static void Main(string[] args)
{
SetupPath(); // current process, soon to be deprecated
// There are several options to initialize the engine, but by default the following suffice:
REngine engine = REngine.GetInstance();
engine.Initialize(); // required since v1.5
// some random weight samples
double[] weight = new double[] { 3.2, 3.6, 3.2, 1.7, 0.8, 2.9, 2, 1.4, 1.2, 2.1, 2.5, 3.9, 3.7, 2.4, 1.5, 0.9, 2.5, 1.7, 2.8, 2.1, 1.2 };
double[] lenght = new double[] { 2, 3, 3.2, 4.7, 5.8, 3.9, 2, 8.4, 5.2, 4.1, 2.5, 3.9, 5, 2.4, 3.5, 0.9, 2.5, 2.7, 2.8, 2.1, 1.2 };
// introduce the samples into R
engine.SetSymbol("weight", engine.CreateNumericVector(weight));
engine.SetSymbol("lenght", engine.CreateNumericVector(lenght));
// set the weights and lenghts as a data frame (regular R syntax in string)
engine.Evaluate("df <- data.frame(id=c(1:length(weight)), weight = weight,lenght = lenght )");
// evaluate and retrieve mean
double avg = engine.Evaluate("mean(df$weight)").AsNumeric().ToArray()[0];
// same for standard deviation
double std = engine.Evaluate("sd(df$weight)").AsNumeric().ToArray()[0];
// NumericVector coeff = engine.Evaluate("coefficients(lm(df$weight ~ df$lenght ))").AsNumeric();
// print output in console
System.Globalization.CultureInfo ci = new System.Globalization.CultureInfo("en-gb");
//Show in console the weight and lenght data
Console.WriteLine(string.Format("Weights: ({0})", string.Join(",",
weight.Select(f => f.ToString(ci)) // LINQ expression
)));
Console.WriteLine(string.Format("Length: ({0})", string.Join(",",
lenght.Select(f => f.ToString(ci)) // LINQ expression
)));
Console.WriteLine(string.Format("Sample size: {0}", weight.Length));
Console.WriteLine(string.Format(ci, "Average: {0:0.00}", avg));
Console.WriteLine(string.Format(ci, "Standard deviation: {0:0.00}", std));
var result = engine.Evaluate("lm(df$weight ~ df$lenght)");
engine.SetSymbol("result", result);
var coefficients = result.AsList()["coefficients"].AsNumeric().ToList();
double r2 = engine.Evaluate("summary(result)").AsList()["r.squared"].AsNumeric().ToList()[0];
double intercept = coefficients[0];
double slope = coefficients[1];
Console.WriteLine("Intercept:" + intercept.ToString());
Console.WriteLine("slope:" + slope);
Console.WriteLine("r2:" + r2);
string fileName = "myplot.png";
CharacterVector fileNameVector = engine.CreateCharacterVector(new[] { fileName });
engine.SetSymbol("fileName", fileNameVector);
engine.Evaluate("png(filename=fileName, width=6, height=6, units='in', res=100)");
engine.Evaluate("reg <- lm(df$weight ~ df$lenght)");
engine.Evaluate("plot(df$weight ~ df$lenght)");
engine.Evaluate("abline(reg)");
engine.Evaluate("dev.off()");
//The file will save in debug directory
Application.Run(new Form1());
// After disposing of the engine, you cannot reinitialize nor reuse it
engine.Dispose();
}
