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Galculator replaced with MATE Calc

August 18, 2020 — BarryK

I received an email from Olivier, informing me that Galculator and Xcalc scientific calculators give an unsatisfactory answer for "cos 90" (where 90 is in degrees). The correct answer is zero, however, Galculator gives "6.12323399574e-17" -- OK, that is pretty close to zero, but really, we do want the calculator to show the exact answer.

Olivier suggested replacing with Calcoo, however, that is written in Java. Instead, I have replaced Galculator with MATE Calc, see project page here:

https://github.com/mate-desktop/mate-calc

I don't know if MATE Calc has other issues, but it does give the correct answer for "cos 90"! 

Note, it is in the Debian repository, as "mate-calc", and is not the latest version.  I am using Debian's DEBs.

EDIT:
I just found this comment:
https://github.com/mate-desktop/mate-calc/issues/38
Quoting:
Any number smaller than 5e-10 is truncated to 0 in the display, although the correct value is held internally (confirm by multiplying the '0' result so that the new result will be > 5e-10).
...so, mate-calc isn't really any better than Galculator. I wonder if that is the same situation with Calcoo?

Hmmm, I might go back to Galculator, as it does quad-precision maths. 

EDIT:
I have gone back to Galculator, and have added Calcoo. The Debian repository has Calcoo 1.3.18, that is written in C for GTK+. That was in 2007 and the author of Calcoo changed to Java:

https://sourceforge.net/projects/calcoo/

Anyway, the old version from 2007 works fine, and is very small, so I have added it to the collection.   

Tags: easy