# Convert double to string with Calculator

I would like to convert double to string using the calculator (or ArcObjects) and get the actual number. Calculator seems to truncate the number at ~15 decimal places but the actual value may be a lot more precise? The only way to i can see the actual value is when i hit the "Get Unique Values" button in the Select by Attributes dialog.

Using a random number obtained from the list of unique Values I can write a simple query that correctly retrieves 13 records:

Shape_Length = 9.999983012676239e-005

The value that shows in the Shape_Length attribute is 0.000100000

if I write the following query by simpley copying this value, it does not retreive any records:

Shape_Length = 0.000100000

Taking this a step further, if i create a column and convert the double values from the Shape_Length field into it, though the numbers apear more precise, they are not identical to the value obtained from the Values list.

When I convert 0.000100000 to a string field using the calculator i get 9.99998301267624E-05

When I query Shape_Length = 9.99998301267624E-05 i do get 13 records in this situation but in other cases i may get less records.

in summary:

Shape_Length value: 0.000100000

Converted to string from Calculator: 9.99998301267624E-05

From Get Unique Values list: 9.999983012676239e-005

that's 3 different numbers. I would like to be basically able to see the same number I see in the Unique Values list in my attribute table. How?

• This may be better asked at Stack Overflow as a pure Python or VBS question
– Midavalo
Sep 20 '16 at 18:50
• See this post about precision/accuracy.
– Paul
Sep 20 '16 at 18:58