# Manipulate duplicates the output

I not sure if the question has been asked or not. I tried to find something similar without success.

I have this small code:

Manipulate[Plot[Sin[a x], {x, 0, 2}], {a, 1, 10}]


The output is ok. when I changed a using the Manipulate controller bar, the output is ok too. But when I used the keyboard to enter value of a and then Enter, I get a duplicate output:

Did I do something wrong to get this output?

Thank you

• I can reproduce that only for Shift+Enter event or numeric keyboard Enter. It always has been a little bit annoying. – Kuba Jan 7 '15 at 19:25
• Very annoying.. – Algohi Jan 7 '15 at 19:28
• Shift+Enter means evaluate the current cell (if it is evaluatable). When you evaluate a Manipulate output, it evaluates to another (instance of a) Manipulate, as well as converting the output cell to an input cell as shown by the In/Out tags in your screen shot. However annoying it is, the behavior is quite consistent with the documented behavior sifht+enter, which must be familiar to any somewhat experienced user. – Michael E2 Jan 7 '15 at 21:13
• Using Enter (Return keyboard button without shift) solves the issue. – Algohi Jan 7 '15 at 22:05
• I use Tab myself, but it changes focus and selects the InputField text. – Michael E2 Jan 7 '15 at 22:10

Your code defines the Control to be a Slider by default. Typing into a different device, the InputField, yields a separate computation and separate output cell.
If you'd like to change the Control for input to be an InputField so you can type different values of a without producing different output cells, try this:
Manipulate[Plot[Sin[a x], {x, 0, 2}], {{a, 5}, InputField}]