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HP49-HP50: list of var in an equation - Gil - 10-02-2022 10:19 PM
I have, in the stack of the calculator, for instance the following equation (all the variables are with power of 1, but their coefficient being not necessarily integers):
'2.55*x1 + 19.07*b + 11*c1 - 50.333*d = k'.
My question: Is there a COMMAND or an easy way to get the list of the variables in the above equation (as the calculator detect those variables when executing STEQ 30 MENU)?
I checked, but could not solve this easy problem.
My apologises in advance if the answer is in the manuals.
Thanks for your help.
Just for infornation:
I try to copy a system of linear in equations from a book into the calculator.
I have to detect the variables and, afterwards, the coefficients of those variables (the latter question is easily solved by setting 1 variable to 1 and the remaining ones to 0).
Regards,
Gil
RE: HP49-HP50: list of var in an equation - DavidM - 10-03-2022 01:08 AM
Try LNAME. It returns its result as an array, which can easily be converted to a list with AXL.
The Advanced Users Reference shows more details about LNAME and how it differs from LVAR, which provides a different take on the variables.
RE: HP49-HP50: list of var in an equation - Gil - 10-03-2022 08:32 AM
Thanks, David, "your" LNAME command is the one I was looking for.
By the way, is there a built-in command or an easy way to get the coefficient of
Y='2.5*x + 7.5*b + 35* c'
apart evaluating Y for
(x=1, b and b = 0)
(b=0, x and c = 0)
(c=1, a and b = 0)?
Regards,
Gil