private void checkSwitchedLogPowRoundTrip(double value) {
          assertEquals("log(pow(x)) = x", value, this.axis.switchedLog10(
                  this.axis.switchedPow10(value)), EPSILON);
          assertEquals("pow(log(x)) = x", value, this.axis.switchedPow10(
                  this.axis.switchedLog10(value)), EPSILON);