title: In tensorflow what is the difference between tf.add and operator (+)?
body: <p>In tensorflow tutorials, I see both codes like <code>tf.add(tf.matmul(X, W), b)</code> and <code>tf.matmul(X, W) + b</code>, what is the difference between using the math function <code>tf.add()</code>, <code>tf.assign()</code>, etc and the operators <code>+</code> and <code>=</code>, etc, in precision or other aspects? </p>