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**LOGE(**//expression//**)**

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| **LOGE** | Returns the natural logarithm. |
| //expression// | A numeric constant, variable, or expression. If the value of the //expression// is less than zero, the return value is zero. The natural logarithm is undefined for values less than zero. |

The **LOGE** (pronounced "log-e") procedure returns the natural logarithm of a numeric //expression//. The natural logarithm of a value is the power to which **e** must be raised to equal that value. The value of **e** used internally by the Clarion library for these calculations is 2.71828182846.

| **Return Data Type:** | REAL |

**Example:**

** !LOGE(2.71828182846)  returns 1**

** !LOGE(1)              returns 0**

**LogVal = LOGE(Val)     !Get the natural log of Val**

**See Also:**

[[log10  return base 10 logarithm .htm|LOG10]]