code: public SDVariable add(String varName, double scalar) {
          val function = sameDiff.f().add(this,scalar);
          return sameDiff.updateVariableNameAndReference(function,varName);
      }
docs: Scalar addition: {@code out = this + scalar}<br>
  Output variable has the same shape as the input variable
  
  @param varName Output variable name
  @param scalar  Scalar for operation
  @return Output variable