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+--- Thread: Using solve and sigma from programming (/thread-16562.html)
Using solve and sigma from programming - photometer - 03-30-2021 12:33 AM
Hello,
I have an equation
pv = cf/(1+r) + cf/(1+r)^1 + cf/(1+r)^2 + ... + cf/(1+r)^n
I have the value of pv, cf and I need to find the value of r. How do I call the CAS.solve() and pass a function that does summation?
BEGIN
LOCAL pv,cf,result;
pv:= 100;
cf:= 10;
result:=CAS.solve(.....); // <- how do I write this?
END;
RE: Using solve and sigma from programming - roadrunner - 03-30-2021 01:43 PM
I deleted my previous post because i had an error in the program.
I'm thinking this:
PHP Code:
EXPORT testsum()
BEGIN
LOCAL pv,cf,result;
pv:=100;
cf:=10;
result:=CAS(EVAL("solve("+pv+" = (sum("+cf+"/(1+r)^n,n,0,∞)),r)"));
return result;
END;
is what you are looking for?
-road
RE: Using solve and sigma from programming - photometer - 03-30-2021 10:53 PM
Thanks very much. It works now.