change in sample2 to support a discussion. I may have forgotten to push it previously.

Author: jmp75

Sample2/Program.cs

@@ -8,86 +8,97 @@
 
 namespace Sample2
 {
- class Program
- {
- static void Main(string[] args)
- {
- // Sample code used for updating the documentation at the codeplex web site.
- using (REngine engine = REngine.GetInstance())
- {
- var e = engine.Evaluate("x <- 3");
- // You can now access x defined in the R environment.
- NumericVector x = engine.GetSymbol("x").AsNumeric();
- engine.Evaluate("y <- 1:10");
- NumericVector y = engine.GetSymbol("y").AsNumeric();
-
- // Invoking functions; Previously you may have needed custom function definitions
- var myFunc = engine.Evaluate("function(x, y) { expand.grid(x=x, y=y) }").AsFunction();
- var v1 = engine.CreateIntegerVector(new[] { 1, 2, 3 });
- var v2 = engine.CreateCharacterVector(new[] { "a", "b", "c" });
- var df = myFunc.Invoke(new SymbolicExpression[] { v1, v2 }).AsDataFrame();
-
- // As of R.NET 1.6, more function call syntaxes are supported.
- var expandGrid = engine.Evaluate("expand.grid").AsFunction();
- var d = new Dictionary<string, SymbolicExpression>();
- d["x"] = v1;
- d["y"] = v2;
- df = expandGrid.Invoke(d).AsDataFrame();
-
- // querying data frames
- engine.SetSymbol("cases", df);
- // As of R.NET 1.6, factor to character expressions work consistently with R
-
- var letterCases = engine.Evaluate("cases[,'y']").AsCharacter().ToArray();
- // "a","a","a","b","b","b", etc. Same as as.character(cases[,'y']) in R
- // This used to return "1", "1", "1", "2", "2", etc. with R.NET 1.5.5
-
- // Equivalent:
- letterCases = df[1].AsCharacter().ToArray();
- letterCases = df["y"].AsCharacter().ToArray();
-
- // Accessing items by two dimensional indexing
- string s = (string)df[1, 1]; // "a"
- s = (string)df[3, 1]; // "a"
- s = (string)df[3, "y"]; // "b"
- // s = (string)df["4", "y"]; // fails because there are no row names
- df[3, "y"] = "a";
- s = (string)df[3, "y"]; // "a"
- df[3, "y"] = "d";
- s = (string)df[3, "y"]; // null, because we have an <NA> string in R
-
- // invoking a whole script
- // engine.Evaluate("source('c:/src/path/to/myscript.r')");
-
- // TODO
- // Date-time objects
-
- }
- }
-
-
- // Investigate use of the Defer method. Deprecated?
- private static string DeferedStatementRepro(REngine engine)
- {
- // Looking at the issues reported in https://rdotnet.codeplex.com/discussions/458547
- // indeed the R.NET documentation page as of 22 Sept 2013 is off as to what Defer method there is.
- // The following memory stream is a workaround out of curiosity: not something intended for ongoing use.
- // With the memory stream workaround, it bombs. 
- // Not sure whether this is because of the conversion to byte, but unlikely to be a false positive.
- string deferedStatement = "x <- 3";
-
- var byteArr = Array.ConvertAll(deferedStatement.ToArray(), c => Convert.ToByte(c));
- using (var stream = new MemoryStream(byteArr))
- {
- // Defer method delays an effect on the R environment.
- var e = engine.Defer(stream);
- // Error: GetSymbol method returns null at the moment.
- // NumericVector x = engine.GetSymbol("x").AsNumeric();
-
- // Evaluates the statement.
- e.ToArray();
- }
- return deferedStatement;
- }
- }
+ class Program
+ {
+ static void Main(string[] args)
+ {
+ // Sample code used for updating the documentation at the codeplex web site.
+ using (REngine engine = REngine.GetInstance())
+ {
+ var e = engine.Evaluate("x <- 3");
+ // You can now access x defined in the R environment.
+ NumericVector x = engine.GetSymbol("x").AsNumeric();
+ engine.Evaluate("y <- 1:10");
+ NumericVector y = engine.GetSymbol("y").AsNumeric();
+
+ // Invoking functions; Previously you may have needed custom function definitions
+ var myFunc = engine.Evaluate("function(x, y) { expand.grid(x=x, y=y) }").AsFunction();
+ var v1 = engine.CreateIntegerVector(new[] { 1, 2, 3 });
+ var v2 = engine.CreateCharacterVector(new[] { "a", "b", "c" });
+ var df = myFunc.Invoke(new SymbolicExpression[] { v1, v2 }).AsDataFrame();
+
+ // As of R.NET 1.6, more function call syntaxes are supported.
+ var expandGrid = engine.Evaluate("expand.grid").AsFunction();
+ var d = new Dictionary<string, SymbolicExpression>();
+ d["x"] = v1;
+ d["y"] = v2;
+ df = expandGrid.Invoke(d).AsDataFrame();
+
+ // querying data frames
+ engine.SetSymbol("cases", df);
+ // As of R.NET 1.6, factor to character expressions work consistently with R
+
+ engine.Evaluate("head(cases)");
+
+ /*
+ x y
+1 1 a
+2 2 a
+3 3 a
+4 1 b
+5 2 b
+6 3 b */
+
+ var letterCases = engine.Evaluate("cases[,'y']").AsCharacter().ToArray();
+ // "a","a","a","b","b","b", etc. Same as as.character(cases[,'y']) in R
+ // This used to return "1", "1", "1", "2", "2", etc. with R.NET 1.5.5
+
+ // Equivalent:
+ letterCases = df[1].AsCharacter().ToArray();
+ letterCases = df["y"].AsCharacter().ToArray();
+
+ // Accessing items by two dimensional indexing
+ string s = (string)df[1, 1]; // "a"
+ s = (string)df[3, 1]; // "a"
+ s = (string)df[3, "y"]; // "b"
+ // s = (string)df["4", "y"]; // fails because there are no row names
+ df[3, "y"] = "a";
+ s = (string)df[3, "y"]; // "a"
+ df[3, "y"] = "d";
+ s = (string)df[3, "y"]; // null, because we have an <NA> string in R
+
+ // invoking a whole script
+ // engine.Evaluate("source('c:/src/path/to/myscript.r')");
+
+ // TODO
+ // Date-time objects
+
+ }
+ }
+
+
+ // Investigate use of the Defer method. Deprecated?
+ private static string DeferedStatementRepro(REngine engine)
+ {
+ // Looking at the issues reported in https://rdotnet.codeplex.com/discussions/458547
+ // indeed the R.NET documentation page as of 22 Sept 2013 is off as to what Defer method there is.
+ // The following memory stream is a workaround out of curiosity: not something intended for ongoing use.
+ // With the memory stream workaround, it bombs. 
+ // Not sure whether this is because of the conversion to byte, but unlikely to be a false positive.
+ string deferedStatement = "x <- 3";
+
+ var byteArr = Array.ConvertAll(deferedStatement.ToArray(), c => Convert.ToByte(c));
+ using (var stream = new MemoryStream(byteArr))
+ {
+ // Defer method delays an effect on the R environment.
+ var e = engine.Defer(stream);
+ // Error: GetSymbol method returns null at the moment.
+ // NumericVector x = engine.GetSymbol("x").AsNumeric();
+
+ // Evaluates the statement.
+ e.ToArray();
+ }
+ return deferedStatement;
+ }
+ }
 }