# Soulver: For all your random calculations

I often find myself doing random calculations and I used to do so part manually and part using Alfred's calculator until Alistair pointed me at Soulver, a desktop/iPhone/iPad app, which is even better.

I thought I'd write some examples of calculations I use it for, partly so I'll remember the syntax in future!

Calculating how much memory Neo4j memory mapping will take up

``````
800 mb + 2660mb + 6600mb + 9500mb + 40mb in GB = 19.6 GB
``````

How long would it take to cover 20,000 km at 100 km / day?

``````
20,000 km / 100 km/day in months = 6.57097681677241832481 months
``````

How long did an import of some data using the Neo4j shell take?

``````
4550855 ms in minutes = 75.84758333333333333333 minutes
``````

Bit shift 1 by 32 places

``````
1 << 32 = 4,294,967,296
``````

Translating into easier to digest units

``````
32381KB / second in MB per minute = 1,942.86 MB/minute
500,000 / 3 years in per hour = 19.01324310408685857874 per hour^2
``````

How long would it take to process a chunk of data?

``````
100 GB / (32381KB / second in MB per minute)  = 51.47051254336390681778 minutes
``````

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