Functions > Symbolic Functions > Example: Logarithmic Integral Functions
Example: Logarithmic Integral Functions
Logarithmic Integral Functions
1. Evaluate li function when x=2.4.
2. Evaluate li function when x=2:
The evaluation returns an expression.
To receive numeric results, you can use decimal digits:
3. Another option for receiving numeric results is to use the float keyword. Evaluate li function when x=ⅇ:
And using the float keyword:
4. li has a single positive zero. Use the assume keyword to solve for positive values of x.
5. Use the limit operator and symbolically evaluate logarithmic integral functions as its argument approaches infinity:
The limits on both sides of branch cut are different:
6. The logarithmic integral function has one singularity point on x=1.
Offset Logarithmic Integral Functions
1. Evaluate the offset logarithmic integral function Li when x=2.4:
2. Evaluate Li when x=ⅇ.
You can see that, similarly to li function, the evaluation returns an expression. To receive numeric results, use the float keyword:
3. Evaluate Li when x=∞ and x=-∞: