Post Reply 
Some issues solving linear equation
06-22-2018, 01:06 PM (This post was last modified: 06-22-2018 01:09 PM by sasa.)
Post: #1
Some issues solving linear equation
While testing Emu48 for another issue, testing certain samples shows some minor issues...

Solving linear equation on 48GX (I'm unaware of ROM version, it is found at hpcalc.org) shows following:

x + y + 2z = -2
3x - y + 14z = 6
x + 2y = -5

x = -.904761904762
y = -2.04761904762
z = .47619047619

This is only one of solution, as this system have infinite number of solutions, however there is no further notice from the calculator about. The solution actually is in form:
x = -4n + 1
y = 2n - 3
z = n

The following synthetic example is much more obvious, the system have no solution:
x - 5y + 3z = -8
0x + 2y + 1z = 3
0x + 0y + 0z = 7

However, emulator returns:
x = -.150793650794
y = 1.5374603175
z = -6.34920634921E-2

This may indicate the method used to solve linear equation (probably inversion matrix). With Gauss-Jordan method of elimination, solution or at least note about it is straightforward.

Perhaps this as well is noted in the calculator's documentation. However, I'm interested what is result of more recent calculators on these synthetic examples, for instance on Prime.
Find all posts by this user
Quote this message in a reply
Post Reply 


Messages In This Thread
Some issues solving linear equation - sasa - 06-22-2018 01:06 PM



User(s) browsing this thread: 1 Guest(s)