在php中显示R数据

Question

I have a issue with showing R results in php.

I dont know how to configure the php file in his echo (); to show the correct result.

# my_rscript3.R
library(class)
require(lattice)
require(ggplot2)
library(caret)
iris2=read.csv("/var/www/html/machine/iris.csv",header = TRUE)  
normalizacion=function(x) {
num=x - min(x) 
denom=max(x) - min(x)    
return (num/denom)
}
iris2_normalizado=as.data.frame(lapply(iris2[1:4], normalizacion))
set.seed(1234)
iris2x=sample(2, nrow(iris2), replace=TRUE, prob=c(0.67, 0.33))
iris2x.training=iris2[iris2x==1, 1:4]
iris2x.test=iris2[iris2x==2, 1:4]
iris2x.trainLabels=iris2[iris2x==1, 5]
iris2x.testLabels=iris2[iris2x==2, 5]
iris2x_pred=knn(train=iris2x.training, test=iris2x.test, cl=iris2x.trainLabels, k=3)
confusionMatrix(iris1x.testLabels,iris1x_pred)

This is my r file and I want to show the the confusionMatrix() like this in a php file

Confusion Matrix and Statistics

            Reference
Prediction   setosa versicolor virginica
  setosa          9          0         0
  versicolor      0         15         0
  virginica       0          1        15

Overall Statistics

               Accuracy : 0.975           
                 95% CI : (0.8684, 0.9994)
    No Information Rate : 0.4             
    P-Value [Acc > NIR] : 7.374e-15

and my php is written like this

<?php
// table.php
  // execute R script from shell
  exec("/usr/lib/R/bin/Rscript my_rscript3.R");
  echo("?????????");
}
?>

Any help to fill the echo("?????????")?