Trident Help

RPN Financial 12 manual · Chapter 15 of 16

Error messages

Every error the calculator can show, what it means and how to fix it.

15.1Clear an error#

When something goes wrong the display shows Error and a number. Press any key to clear it. That key is only used to clear the message, so press it again if you also wanted it to act. The stack keeps the values it had before the error.

Example 15.1

Divide by zero

  1. Key in 0 and press 1/x.

    01/x
Result of the example "Divide by zero" The display shows:   Error 0 /  0.00 /  0.00 /  0.00 /  0.00.
You should seeError 0
Error 0: 1 divided by 0. The display shows:   Error 0 /  0.00 /  0.00 /  1.00 /  0.00.
Error 0: 1 divided by 0.

15.2All error numbers#

MessageWhat it meansHow to fix
Error 0An improper math operation: division by zero, square root of a negative number, logarithm of zero or less, a negative base with a fractional power, a negative factorial, or Δ% and %T with a base of zero.Check the numbers in X and Y. Press gLSTxENTER (LSTx) to recover the number you used.
Error 2A statistics error: no data for the mean, fewer than two points for a standard deviation or fitted line, or all x values equal.Enter more data with Σ+. Clear with CLEAR Σ and start again if the data is wrong.
Error 3IRR could not settle on a rate, or a register number was out of range.Check the cash flows. Try fewer or simpler flows.
Error 4A program problem: memory is full (99 lines) or GTO names a line that does not exist.Check the line number. Clear the program and record a shorter one.
Error 5No solution for the financial problem: an unsolvable TVM equation, a rate of −100% or less, AMORT with a part payment, a depreciation year of 0 or a life of 0, or a bond yield that cannot be found.Check the signs of PV, PMT and FV, and that the values make sense (a payment that can never repay the loan).
Error 6A cash-flow problem: more than 20 flows, or a bad Nj.Use no more than CF₀ and 19 CFj. Nj must be a whole number from 1 to 99.
Error 7IRR needs at least one positive and one negative cash flow.Check the signs of the flows.
Error 8An invalid date, or a bond maturity not after settlement.Check the date format (M.DY or D.MY) and that the date exists.
Example 15.2

Standard deviation with one point

  1. Enter a single point and press g, s.

    1Σ+gs.
Result of the example "Standard deviation with one point" The display shows:   Error 2 /  0.00 /  0.00 /  0.00 /  1.00.
You should seeError 2
Example 15.3

No solution for the payment problem

  1. Pay nothing, never repay: i cannot be found.

    10n5i100PV0PMT100FVi
Result of the example "No solution for the payment problem" The display shows:   Error 5 /  5.00 /  100.00 /  0.00 /  100.00.
You should seeError 5
Example 15.4

Wrong sign convention hides the answer

  1. If PV and FV have the same sign and PMT is 0, the rate cannot be found.

    10n5i100CHSPV0PMT100CHSFVi
Result of the example "Wrong sign convention hides the answer" The display shows:   Error 5 /  5.00 / -100.00 /  0.00 / -100.00.
You should seeError 5
Example 15.5

IRR without a sign change

  1. Only positive flows.

    1000gCF₀PV500gCFjPMTfIRRFV
Result of the example "IRR without a sign change" The display shows:   Error 7 /  0.00 /  0.00 /  1,000.00 /  500.00.
You should seeError 7
Error 8: 30 February 2026 is not a date. The display shows:   Error 8 /  0.00 /  0.00 /  2.30 /  1.00.
Error 8: 30 February 2026 is not a date.

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