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+//Example of simple columnar ransposition technique with multiple rounds
+
+// Move scilab to current file directory
+[u,t,n] = file()
+n = strcat(n)
+file_name = basename(n)+fileext(n)
+file_name = strcat(file_name)
+ind=strindex(n,file_name)
+path = part(n,1:ind-1)
+chdir(path)
+
+exec("Chapter_2.sci")
+
+pt = "Come home tomorrow"
+disp("Original plaintext message:")
+disp(pt)
+
+//function from dependency file
+l = length(remove_spaces(pt))
+//disp(l)
+
+rounds = 2
+col_order = [4 6 1 2 5 3]
+col = 6
+row = l/6
+    if modulo(l,6)>0 then
+        row=row+1
+    end
+
+for r=1:rounds
+    printf("\nRound %d:",r)
+
+    //function from dependency file
+    pt_mat = message_rectangle(pt)
+    
+    disp("")
+    disp("Plaintext:")
+    disp(pt)    
+    disp("Plaintext message rectangle:")
+    printf("\n")
+    for i=1:col
+        printf(" %d ",i)
+    end
+    disp(pt_mat)
+    
+    k=1
+    
+    ct=[]
+    //Convert to ciphertext
+    for n = 1:length(col_order)
+        j = col_order(n)
+        for i=1:row
+            pos = (i-1)*col + j
+            if pos>l then
+                continue
+            end
+            ct(k)=pt_mat(i,j)
+            k=k+1
+        end
+    end
+    disp("Ciphertext:")
+    ct = strcat(ct)
+    disp(ct)
+    pt = ct
+    disp("")
+end
+
+disp("Final ciphertext:")
+disp(ct)