the_log | Replace console.log with log in your Rails

Unfortunately, no operation to check whether x is within (-σ, σ) will be differentiable and therefore σ cannot be learnt via any gradient descent method. Specifically, it is not possible to compute the gradients with respect to self.threshold_level because tf.math.less is not differentiable with respect to the condition.

Regarding the element-wise conditional, you can instead use tf.where to select elements from f_True(input) or f_False(input) according to the component-wise boolean values of the condition. For example: