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Logarithm: natural / arbitrary base (log)

Description

Returns the base-e logarithm of the selected number. Optionally, you can add a second argument to calculate the log base x of a given number.

How does it work in the search window?

Select Create column in the search window toolbar, then select the Logarithm: natural / arbitrary base operation. You need to specify at least one argument:

Argument

Data type

Argument

Data type

Argument mandatory

integer, float

Base

integer, float

The data type of the values in the new column is float.


Example


We want to get the base-e logarithm of the numbers in our posNumbers1 column. To do it, we will create a new column using the Logarithm: natural / arbitrary base operation.

First, we must transform the string values in the posNumbers1 column into a data type integer. To do it, create a new column using the To Int operation. Call the new column integerValues.

 

Now, create another column using the Logarithm: natural / arbitrary base operation. The arguments needed to create the new column are:

  • Argument integerValues column

 

Click Create column and you will see the following result:

How does it work in LINQ?

Use the operator select... as...  and add the operation syntax to create the new column. This is the syntax for the Logarithm: natural / arbitrary base operation:

  • log(number)

  • log(base_number, number)

Example

You can copy the following LINQ script and try the above example on the my.upload.sample.data table.

from my.upload.sample.data select split(message, ";", 17) as posNumbers1 select int(posNumbers1) as integerValues select log(integerValues) as loge