Java REXP类代码示例

import org.rosuda.REngine.REXP; //导入依赖的package包/类
/**
 * @return available R commands
 */
public String[] listCommands() {
    silentlyEval(".keyWords <- function() {n <- length(search());result <- c();for (i in 1:n) {result <- c(result,ls(pos=i,all.names=TRUE))}; result}");
    REXP rexp = silentlyEval(".keyWords()");
    String as[] = null;
    try {
        if (rexp != null && (as = rexp.asStrings()) != null) {
            return as;
        } else {
            return null;
        }
    } catch (REXPMismatchException ex) {
        log(HEAD_ERROR + ex.getMessage() + "\n  listCommands()",
                Level.ERROR);
        return null;
    }
}
 

import org.rosuda.REngine.REXP; //导入依赖的package包/类
/**
 * Executes an R function (return: String)
 * 
 * @param function
 *        name of the R function
 * @param parameters
 *        array of parameters required by the function
 * 
 *        TODO: make more generic - not just for Strings ...
 */
public static String executeStringFunction(RConnection conn, String function, String[] parameters) {

    try {
        // create request
        String request = "try(" + function + "(";
        for (String parameter : parameters) {
            request += parameter + ",";
        }
        // remove last ","
        request = request.substring(0, request.length() - 1);
        request += "))";
        // execute function
        REXP xp = conn.parseAndEval(request);
        if (xp.inherits("try-error")) {
            close(conn);
            throw new IOException("failed to execute function '" + function + "'; \nrequest: " + request
                    + "; \nError: " + xp.asString());
        }
        String retval = xp.asString();
        return retval;
    }
    catch (Exception e) {
        return null;
    }
}
 

import org.rosuda.REngine.REXP; //导入依赖的package包/类
private String[][] asStringMatrix(final REXP rexp) throws REXPMismatchException {
    final String[] ct = rexp.asStrings();
    final REXP dim = rexp.getAttribute("dim");
    if (dim == null) {
        throw new REXPMismatchException(rexp, "matrix (dim attribute missing)");
    }
    final int[] ds = dim.asIntegers();
    if (ds.length != 2) {
        throw new REXPMismatchException(rexp, "matrix (wrong dimensionality)");
    }
    final int m = ds[0], n = ds[1];

    final String[][] r = new String[m][n];
    // R stores matrices as matrix(c(1,2,3,4),2,2) = col1:(1,2), col2:(3,4)
    // we need to copy everything, since we create 2d array from 1d array
    int k = 0;
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < m; j++) {
            r[j][i] = ct[k++];
        }
    }
    return r;
}
 

import org.rosuda.REngine.REXP; //导入依赖的package包/类
private int[][] asIntegerMatrix(final REXP rexp) throws REXPMismatchException {
    final int[] ct = rexp.asIntegers();
    final REXP dim = rexp.getAttribute("dim");
    if (dim == null) {
        throw new REXPMismatchException(rexp, "matrix (dim attribute missing)");
    }
    final int[] ds = dim.asIntegers();
    if (ds.length != 2) {
        throw new REXPMismatchException(rexp, "matrix (wrong dimensionality)");
    }
    final int m = ds[0], n = ds[1];

    final int[][] r = new int[m][n];
    // R stores matrices as matrix(c(1,2,3,4),2,2) = col1:(1,2), col2:(3,4)
    // we need to copy everything, since we create 2d array from 1d array
    int k = 0;
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < m; j++) {
            r[j][i] = ct[k++];
        }
    }
    return r;
}
 

import org.rosuda.REngine.REXP; //导入依赖的package包/类
@Override
public boolean[] getBooleanVector(final String variable) {
    try {
        final REXP rexp = engine.unwrap().eval(variable);
        if (allIsNa(rexp)) {
            return null;
        } else {
            final int[] ints = rexp.asIntegers();
            final boolean[] booleanVector = new boolean[ints.length];
            for (int i = 0; i < ints.length; i++) {
                booleanVector[i] = ints[i] > 0;
            }
            return booleanVector;
        }
    } catch (final REXPMismatchException e) {
        throw new RuntimeException(e);
    }
}
 

import org.rosuda.REngine.REXP; //导入依赖的package包/类
@Override
public boolean[][] getBooleanMatrix(final String variable) {
    try {
        final REXP rexp = engine.unwrap().eval(variable);
        if (allIsNa(rexp)) {
            return null;
        } else {
            final double[][] matrix = rexp.asDoubleMatrix();
            final boolean[][] booleanMatrix = new boolean[matrix.length][];
            for (int i = 0; i < matrix.length; i++) {
                final double[] vector = matrix[i];
                final boolean[] booleanVector = new boolean[vector.length];
                for (int j = 0; j < vector.length; j++) {
                    booleanVector[j] = vector[j] > 0;
                }
                booleanMatrix[i] = booleanVector;
            }
            return booleanMatrix;
        }
    } catch (final REXPMismatchException e) {
        throw new RuntimeException(e);
    }
}
 

import org.rosuda.REngine.REXP; //导入依赖的package包/类
/**
 * Evaluate script
 * @return R-Expression
 */
public REXP eval () {
  REXP result = null;
  
  try {
    open();
    
    result = mRC.eval(mScript);
  }
  catch (RserveException e) {
    LOG.warning(String.format("RRequest: %s", e.getMessage()));
  }
  finally {
    close();
  }
  
  return result;
}
 

import org.rosuda.REngine.REXP; //导入依赖的package包/类
/**
 * Check for package loaded in R environment.
 * 
 * @param pack
 *            R package name
 * @return package loading status
 */
public boolean isPackageLoaded(String pack) {
    silentlyVoidEval(loadedpacks + "<-.packages()", false);
    boolean isloaded = false;
    try {
        REXP i = silentlyEval("is.element(set=" + loadedpacks + ",el='"
                + pack + "')");
        if (i != null) {
            isloaded = i.asInteger() == 1;
        }
    } catch (REXPMismatchException ex) {
        log(HEAD_ERROR + ex.getMessage()
                + "\n  isPackageLoaded(String pack=" + pack + ")",
                Level.ERROR);
    }
    if (isloaded) {
        log(_PACKAGE_ + pack + " is loaded.", Level.INFO);
    } else {
        log(_PACKAGE_ + pack + " is not loaded.", Level.INFO);
    }

    // silentlyEval("rm(" + loadedpacks + ")");
    return isloaded;
}
 

import org.rosuda.REngine.REXP; //导入依赖的package包/类
/**
 * Launch R command and return value.
 * 
 * @param expression
 *            R expresison to evaluate
 * @param tryEval
 *            encapsulate command in try() to cacth errors
 * @return REXP R expression
 */
public REXP eval(String expression, boolean tryEval) {
    // GLG HACK: Less verbosity when no error.
    // log(HEAD_EVAL + (tryEval ? HEAD_TRY : "") + expression, Level.INFO);

    REXP e = silentlyEval(expression, tryEval);

    for (UpdateObjectsListener b : updateObjects) {
        b.update();
    }

    // GLG HACK: Less verbosity when no error.
    // if (e != null) {
    // log(__ + e.toDebugString(), Level.INFO);
    // }

    return e;
}
 

import org.rosuda.REngine.REXP; //导入依赖的package包/类
/**
 * 
 * @param robject
 *            R object name
 * @return R type of object
 */
public String typeOf(String robject) {
    if (robject == null) {
        return "NULL";
    }
    for (String t : types) {
        REXP is = silentlyEval("is." + t + "(" + robject + ")");
        try {
            if (is != null && is.asInteger() == 1) {
                return t;
            }
        } catch (REXPMismatchException ex) {
            log(HEAD_ERROR + "[typeOf] " + robject + " type unknown.",
                    Level.ERROR);
            return null;
        }
    }
    return "unknown";
}
 

import org.rosuda.REngine.REXP; //导入依赖的package包/类
/**
 * Set R list in R env.
 * 
 * @param varname
 *            R list name
 * @param data
 *            numeric data in list
 * @param names
 *            names of columns
 */
public boolean set(String varname, double[][] data, String... names) {
    RList list = buildRList(data, names);
    log(HEAD_SET + varname + " <- " + toString(list), Level.INFO);
    try {
        synchronized (connection) {
            connection.assign(varname, REXP.createDataFrame(list));
        }
    } catch (REXPMismatchException re) {
        log(HEAD_ERROR + " RList " + list.toString()
                + " not convertible as dataframe.", Level.ERROR);
        return false;
    } catch (RserveException ex) {
        log(HEAD_EXCEPTION + ex.getMessage() + "\n  set(String varname="
                + varname + ",double[][] data, String... names)",
                Level.ERROR);
        return false;
    }
    return true;
}
 

import org.rosuda.REngine.REXP; //导入依赖的package包/类
/**
 * Get an R connection
 * 
 * @param host
 * @param workspace
 * @return {@link RConnection} rConnection - a connection to RServer
 */
private static RConnection getRServeConnection(String host, String workspace) {

    try {
        // establish R connection
        RConnection conn = new RConnection(host);
        // check connection
        if (conn == null || !conn.isConnected())
            throw new IOException("Failed to establish RServe connection");

        // set workspace
        if (workspace != null) {
            REXP xp = conn.parseAndEval("try(setwd('" + workspace.replace("\\", "\\\\") + "'))");
            if (xp.inherits("try-error"))
                throw new IOException("Failed to load R workspace; \nError: " + xp.asString());
        }
        return conn;
    }
    catch (Exception e) {
        return null;
    }
}
 

import org.rosuda.REngine.REXP; //导入依赖的package包/类
@Override
public REXP blockDiscreteFunction(REXPInteger ids, REXPString... values) {
	RList data = new RList();
	data.add(ids);
	data.setKeyAt(0, "ids");
	StringBuilder valueNames = new StringBuilder();
	for(int i = 0 ; i < values.length ; i++) {
		data.add(values[i]);
		valueNames.append("\"values"+i+"\",");
		data.setKeyAt(i+1, "values"+i);
	}
	
	String variableNames = valueNames.substring(0, valueNames.length()-1);
	try{
		synchronized(engine){
			engine.assign("data", REXP.createDataFrame(data));
			return engine.parseAndEval("blockDiscreteFunction(data,c(\"ids\"),c(" + variableNames + "))");
		}
	}catch(Exception e) {
		throw new REngineException("Unexpected error while executing blockDiscreteFunction", e);
	}
}
 

import org.rosuda.REngine.REXP; //导入依赖的package包/类
@Override
public REXP blockFunction(REXPInteger ids, REXPDouble... values) {
	
	RList data = new RList();
	data.add(ids);
	data.setKeyAt(0, "ids");
	StringBuilder valueNames = new StringBuilder();
	for(int i = 0 ; i < values.length ; i++) {
		data.add(values[i]);
		valueNames.append("\"values"+i+"\",");
		data.setKeyAt(i+1, "values"+i);
	}
	
	try{
		synchronized(engine){
			engine.assign("data", REXP.createDataFrame(data));
			return engine.parseAndEval("blockFunction(data,c(\"ids\"),c("+ valueNames.substring(0, valueNames.length()-1) +"))");
		}
	}catch(Exception e) {
		throw new REngineException("Unexpected error while executing blockFunction", e);
	}
}
 

import org.rosuda.REngine.REXP; //导入依赖的package包/类
@Override
public REXP blockFunction(REXPInteger ids, REXPDouble... values) {
	
	RList data = new RList();
	data.add(ids);
	data.setKeyAt(0, "ids");
	StringBuilder valueNames = new StringBuilder();
	for(int i = 0 ; i < values.length ; i++) {
		data.add(values[i]);
		valueNames.append(format("\"values%d\",", i));
		data.setKeyAt(i+1, format("values%d",i));
	}
	
	String variableNames = valueNames.substring(0, valueNames.length()-1);
	REngine engine = null;
	try {
		engine = rConnectionFactory.getConnection();
		engine.assign("data", REXP.createDataFrame(data));
		return engine.parseAndEval(format("blockFunction(data,c(\"ids\"),c(%s))", variableNames));
	}catch(Exception e) {
		throw new REngineException("Unexpected error while executing blockFunction", e);
	} finally {
		rConnectionFactory.releaseConnection(engine);
	}
}