Tag: gnome

This is why we still have real calculators…

gnome-calculator fail

This is about scientific notation, and how Gnome Calculator still doesn’t do it correctly.

So I was checking a simple calculation today, and couldn’t find a proper calculator, so I reached for gnome-calculator on the desktop. That was a mistake.

It seems to think that

8×10¹²÷6×10⁹

comes to

1.333333333×10²¹

which is not correct. It would, if I’d  typed it as:

8×1×10¹²÷6×1×10⁹

You can only get the right answer (1333.333…) if you type

(8×10¹²)÷(6×10⁹)

so it’s clear that gnome-calculator isn’t apply the right exponentiation operator precedence when you hit ‘×10y’. It would have been so much better if gnome-calculator supported ‘E’ scientific notation (1.333E21 for 1.333×10²¹).

A bug is filed, but I don’t think I trust it any more. I’m looking at having a proper calculator again, or maybe invest in one of the delightful tiny HP clones from SwissMicros.com.

HP 49G

Almost forgot that I had a barely-used HP 49G in the cupboard. It was barely used because the thing eats AAA batteries. Who knew that Dollarama would have a pair of NiMH AAAs for only $2?

Update, 2021: Use galculator instead. It does the right thing, and supports RPN like a calculator should. You don’t need to remember any precedence rules when you have The Truth.

It’s not as cold as you’d think

I use Gnome Weather Report, an applet that shows the local temperature and weather conditions on my desktop. For the last few days, it’s been showing something really weird: celsius.png. It’s nothing like -17°C here; it’s nearer 0°C, according to Environment Canada.

Things become clearer when you change the view to Fahrenheit view: fahrenheit.png. It’s clear that the sensor or protocol is broken, but is being mis-interpreted as a zero signal.

As an avid RISKS reader, I know that confusing zero and null values is pretty much unforgivable. I’ve wired up enough 4-20mA current loop instruments to know that having a zero-value signal being the same as a no signal value is bad.

But there’s no real risk here. I mean, I could always go outside and find that it’s not 17°C. You don’t need a weatherman, as Bob said.