Added basic print function

1 files changed, 26 insertions, 3 deletions

diff --git a/R/tf.R b/R/tf.R
index f811b6c..fb722fd 100644
--- a/R/tf.R
+++ b/R/tf.R
@@ -1,4 +1,4 @@
-# S3 class for defining trasnfer functions
+# S3 class for defining transfer functions
 tf <- function(num=c(1),den=c(1),Ts=1){
   out <- list(num=num,den=den,Ts=Ts)
   class(out) <- "tf"
@@ -6,7 +6,30 @@ tf <- function(num=c(1),den=c(1),Ts=1){
 }
 
 # Display the Transfer Function
-print.tf <- function(G){
-  
+print.tf <- function(G){ 
+  cat("Transfer Function \nG(q^{-1}) = B(q^{-1})/A(q^{-1}) \n\n")
+  cat("A(q^{-1}) = ")
+  for(i in seq_along(G$den)){
+    if(i-1==0){
+      cat(G$den[i])
+    } else{
+      if(G$den[i]>0)
+        cat("+")
+      cat(G$den[i],"q^{-",i-1,"}",sep="")
+    }
+    cat("\t")
+  }
+  cat("\n")
+  cat("B(q^{-1}) = ")
+  for(i in seq_along(G$num)){
+    if(i-1==0){
+      cat(G$num[i])
+    } else{
+      if(G$num[i]>0)
+        cat("+")
+      cat(G$num[i],"q^{-",i-1,"}",sep="")
+    }
+    cat("\t")
+  }
 }