磁针偏差计

例句：

1. 1. The compass deviation indicator on the map shows the direction of the magnetic field.
   地图上的指南针偏差计显示了磁场的方向。
2. 2. The compass deviation indicator was used to help navigate during the long journey.
   在漫长的旅程中，指南针偏差计被用来帮助导航。
3. 3. The compass deviation indicator is essential for mariners to determine their location accurately.
   指南针偏差计对于航海家来说至关重要，以便准确地确定他们的位置。