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Newton's method with an iteration table — a TI-84 Plus CE program

By E-Code · updated

NEWTTBL is a TI-BASIC program for the TI-84 Plus CE. Type any f(X) and a starting guess: prints every Newton iterate in a table (central-difference derivative), then the root to 9 decimals, f(root) and the iteration count; reports a flat spot, divergence or no convergence.

What it asks for and what it shows

It asks for 2 values at its prompts. In the example below it shows X, ITERATIONS, 1 , 2 , 3 .

Example run

One of its oracle test cases: “x^3-2x-5 from 2”. The inputs are typed in order, and the results are the values the case expects on the screen.

StepValue
You enter
Input 1X^3-2X-5
Input 22
The screen shows
X=2.094551482
ITERATIONS=4
1 2.1
2 2.094568
3 2.094551

How it's checked

7 test cases, each checked against an independent method. Replayed key by key on a virtual TI-84 Plus CE, they make 41 checks.

How E-Code checks every program

Run it or put it on your calculator

Related programs

All TI-84 Plus CE math programs · All TI-84 Plus CE programs