14   Saved Work, Clearing, and Troubleshooting

SpicyRPN resumes the calculator you left, including unfinished work. That is useful when a calculation spans several sessions, but it also means that reopening the application is not a fresh start. An old financial input, a pending storage command, or an unfinished exponent can still determine what the next key does.

When something looks wrong, first read the mode, flags, and status message. Then identify whether you need to finish an entry, cancel a command, correct a calculation, or clear a particular bank. These are different operations. This chapter provides a way to choose among them without discarding unrelated work.

14.1   What is saved automatically

The application saves actions as you perform them, including individual entry keystrokes. There is no separate Save command and no need to press ENTER merely to preserve a partly typed number. Successful actions save their numerical and presentation changes together. The application does not depend on receiving a final quit notification to save the last key.

Saved work belongs to the application on the current device. It is held in a local database, not synchronized between your Mac, iPhone, and iPad by a calculator account. The current interface has no named calculation files, export/import command, cloud synchronization, or user-facing history browser. Keep the original observations, transaction inputs, and any results you need outside the calculator as appropriate to your work.

The full-stack inspector is temporary: it closes when the application leaves the active state, and does not reopen merely because it was open before. Open it again with the display triangle to inspect the retained stack. Window dimensions can change the layout and scientific-notation fallback without changing a value. A saved horizontal scroll position is a viewing preference, not a stored numerical change.

The database also retains information about how reachable values were calculated. That information does not provide an undo button, an earlier version of each memory bank, or a browsable calculation tape. In particular, Last X and Last Y hold saved previous RPN operands, distinct from the current stack positions X (S0) and Y (S1). LAST X/Y recall those operands under their specific rules; they do not restore a complete earlier calculator state.

14.2   Independent workspaces and shared data

RPN and ALG have independent working areas. Selecting the other mode does not evaluate an expression, finish a number, copy the displayed value, or clear the workspace you leave. Return to the earlier mode to continue its entry. RPN’s Last registers and ALG’s ANS are independent recovery aids, not two names for one previous result.

The settings and memory banks in table 14.1 are shared. Storing a new value in ordinary R2 in ALG changes what RPN later recalls from R2. Changing working precision or the display count in either mode affects subsequent work in both. Changing DEG to RAD changes the shared angle choice, but does not rewrite a trigonometric function already inserted into an ALG expression; that function retains its original unit. See section 4.5 and chapter 5.

An ordinary mode selection cancels active shifts and pending command prefixes. For RPN, it also makes the next bare TVM key a store. Consequently, switching away and back is not equivalent to simply pausing immediately after a financial store. When resuming a financial task, use explicit STO/RCL and the solve procedure in section 11.4 if the next bare key’s purpose is uncertain.

The ALG \(\Delta \)FIX prompt is an exception to immediate mode switching: the first mode-button press cancels that prompt and leaves ALG selected. Press the requested mode again to switch.

The examples use CLEAR on orange \(1/x\) in RPN and the unshifted editing key in ALG. Prepare their stated precision, display, and stack settings with the procedures in section 3.1 and chapter 5; no example depends on old memory contents. Angle units, date order, and payment timing do not affect the example results in this chapter.

Complex mode and representation changes require extra care. Unlike an ordinary RPN/ALG switch, they validate and commit pending numeric entries in both workspaces before changing the shared setting. They do not evaluate a whole ALG expression. If an unfinished ALG exponent prevents the change while RPN is selected, return to ALG and complete, correct, or clear that entry. Section 8.1 explains this case.

14.3   Resuming an unfinished entry

After reopening, check these items before typing:

1.

Read any saved-state error first. Follow section 14.9 if the message concerns saving or restoring memory.

2.

Check the selected RPN/ALG button, any open tool, and the flags for a shift or pending command. A digit may be a register selector or FIX count rather than the next digit of your number.

3.

Read ENTRY and the displayed literal. In RPN, ENTRY means a number is being entered. In ALG it means the whole expression is unfinished, even when no individual number is being typed.

4.

Continue the intended entry, cancel the pending command, or deliberately clear the appropriate working area. Closing and reopening does none of those things for you.

Trailing zeros, a trailing decimal point, an exponent marker and its sign, and the selected complex component can all be resumed. Once an entry has been committed, new digits follow the normal next-operand rules rather than appending to the formatted result. In RPN the reserved stack lift has already happened before a saved partial number reappears; continuing its digits does not lift again.

If a tool panel reopens, its fields may contain an unfinished or invalid draft. Edit those fields and Apply, or Close without applying. Entering digits in a field does not enter a calculator operand. A validation message can also be restored with the panel. Reopening is not an Apply action; the proposed settings have not taken effect merely because their draft fields were saved.

14.4   Cancel the pending operation before editing

A pending prefix temporarily changes the meaning of the next key. Use its indicator, not the large number alone, to decide what to press. The header’s CANCEL dismisses any pending shift or command in one press, including CPT or a command and shift selected together. It preserves unfinished numeric entry, the ALG expression, all values, and settings, and dismisses a displayed error. CANCEL also appears while an ALG worksheet is active. An unfinished number or expression alone does not make it appear. Its position remains fixed beside the branding even when CAL is visible.

An ALG worksheet has its own CANCEL, also available through physical Escape. Worksheet cancellation returns to the suspended main expression and discards that worksheet’s unaccepted drafts, not earlier accepted fields, ANS updates, or completed operations. If you relaunch before canceling, the active worksheet and its exact draft resume. Review accepted financial fields carefully: their ENTER action already stored the corresponding bank register. See section 4.12.

Table 14.2 lists other cancellation methods. CANCEL works for every shift or command in the table, including a notation digit selector; use a tool’s Close control for an open tool or the worksheet’s CANCEL control for an open worksheet.

Outside a tool, worksheet, or inspector, physical Escape cancels a pending shift, command, or displayed error without clearing a value. With none of those present, it performs CLx instead. Do not press Escape repeatedly as a general acknowledgment: the next press may clear the operand. Selecting the current entry-mode button is another way to cancel ordinary prefixes while retaining the workspace, subject to the FIX rule above.

CLx or CLEAR can also cancel an ordinary pending STO/RCL, and ALG FUNC, instead of performing their clear. After cancellation, repeat the intended clearing sequence if you still want to erase the operand or workspace. Use CANCEL whenever you want to dismiss the selection without considering shift routing or the clear key’s other functions.

14.5   Choose the smallest clear that fits

These clears assume that no shift or command is pending. Backspace edits the current entry, CLx clears one operand, and CLEAR clears the active working area. None is an ordinary-memory reset. For the RPN rows below, X is S0 and Y is S1; Last X and Last Y are separately saved previous operands.

In a complex entry, backspace edits the selected component; clearing all its characters leaves that component zero within the pair. CLx acts on the whole operand. To change just one accepted component, use Re/Im as described in section 8.2.

CLx is not DROP. After CLx in RPN, typing a new number lifts the zero into Y, moving an earlier Y deeper. To replace an accepted X while retaining Y as the other operand, use orange DROP on the roll-down key, then type the replacement. The complete correction examples in section 3.8 demonstrate this distinction.

Clear a memory bank deliberately

There is no one-key factory reset. MCLR is a selected group clear, not a reset of every bank, both workspaces, and all preferences. Cleared banks cannot be reconstructed with LAST X/Y or ANS. Clear only the data that the new task is intended to replace.

The sequences in table 14.4 clear entire groups, not individual register addresses. Start with no pending prefix and press each sequence as shown. For the full group-selection and cancellation rules, see section 6.10.

The three memory-bank clears preserve an unfinished numeric entry, expression, and stack; they do not first commit the entry. Their flags disappear because the entries are removed. A stored zero also counts as occupied, so overwriting a value with zero is not equivalent to emptying its bank. Group clearing does not reset settings or BEGIN/END.

Dedicated RPN clears offer narrower choices. Orange Sigma-plus, \(\mathrm {CL}_{\Sigma }\), removes statistics; orange FV, \(\mathrm {CL}_{fin}\), removes only financial registers; blue FV, \(\mathrm {CL}_{cf}\), removes cash flows and stores \(n=0\). These commands first finish an active numeric entry. CLcf therefore turns off CF but leaves FIN present. CLfin can leave cash flows whose selected n must be set again before use. None of these clears removes an earlier ordinary-memory copy of a statistical total.

In ALG, orange FV and blue FV have those same bank-clear scopes while preserving the main expression. For statistics, open STAT, select Clear statistics, and press CLEAR STATISTICS. This removes the bank and updates ANS to zero; the main expression and ordinary copies in R4–R9 remain. Worksheet CANCEL afterward closes the worksheet without undoing that completed clear.

14.6   Prepare a fresh problem without resetting the application

Do not toggle BGN, CMPLX, or a representation setting blindly. Read the current flag or labels first, then change only what differs from the intended starting state. A fresh problem is a known set of relevant inputs, not necessarily an empty calculator.

First close any tool or inspector, cancel pending input, and select the intended entry mode. Set the required working precision, notation, angle unit, and complex setting. Then clear the working area and initialize the inputs that belong to the task:

• Arithmetic or a new ALG expression: clear the active stack or expression. Retained memory flags need not be removed when the calculation does not use those banks.
• Statistics: clear statistics before entering a new data set. Stack CLEAR alone leaves all earlier observations in the accumulators.
• TVM: clear or explicitly replace the financial inputs and check BGN. Set each of the four quantities used by the target solve, including deliberate zeros. CLEAR does not remove an old PMT or FV.
• NPV/IRR: CF0 starts a new list. Include zero-flow periods, set the periodic rate or guess explicitly, and check n before evaluating a saved list.
• Other financial tools: explicitly store their required inputs. AMORT uses elapsed payments in n; simple interest uses days; depreciation uses useful life. The same register names do not imply the same input meanings.

14.7   Diagnose an unexpected result

Locate the first step that differs from the intended calculation. Compare an actual stored value with an actual stored value, or compare rounded displays at the same notation and digit count. If you compare another calculator, also match its entry, financial, date, and rounding conventions; a matching function name is not enough.

Some limitations are properties of the numerical methods rather than entry mistakes. Custom complex special-function algorithms and raw-sum statistical formulas can lose accuracy through cancellation. The relevant subject chapters describe their numerical limits; a longer readout alone cannot resolve them.

14.8   Recover from a calculation error

A calculation error is different from a storage failure. An operand may be outside a function’s domain, an expression may be incomplete, or a solver may be unable to find a result. Read the exact message before clearing it. The next enabled calculator key normally clears the message and performs that key’s action; it is not merely an acknowledgment key. Physical Escape can dismiss an error without performing arithmetic, provided that a message or prefix is still active.

An attempted operation can finish numeric entry before detecting its error. The retained operand can therefore be correct even though ENTRY has changed. In RPN, check X (S0) and Y (S1) before backspacing: with entry no longer active, backspace is CLx. In ALG, a committed number is an expression element, so backspace can remove it as a whole rather than remove its final digit. A failed ALG evaluation retains the expression and does not replace ANS.

Interpret the kind of failure

For missing operands, supply the required input or replace the incomplete expression. For a domain error, check signs, integer requirements, zero divisors, and whether the selected real or complex function is appropriate. Statistics may need more observations or nonzero variance; financial tools may require explicitly stored registers even when a recall of an unset register would show zero. These are input conditions, not requests for more display digits.

A convergence or bracketing error describes an unsuccessful numerical search. Check the model, scale, and any IRR bounds; it does not by itself prove that no mathematical root exists. A capacity or expression-limit message requires a smaller problem or a different decomposition. Unlimited RPN still needs enough actual operands, and cyclic roll is unavailable with an unlimited stack.

RPN can also display NaN, \(\infty \), or \(-\infty \) from basic arithmetic without a separate rejected-command message. NaN means not a number. Treat these as nonfinite values, not ordinary results. Check the function’s domain and replace or clear the affected operand before continuing. ALG rejects nonfinite expression results. Complex mode extends some domains but does not make division by zero or every singular function finite.

For \(\Sigma +\) or \(\Sigma -\), the message Statistics samples must be finite means a sample’s real component is NaN or infinity. Statistics totals must be finite means an existing total is nonfinite or the proposed update would produce one. Both errors preserve the statistical bank; no sample is partly added or removed. Correct the operands and retry, or clear and re-enter the observations if the saved bank already contains nonfinite totals. See chapter 10.

The warning Used real portion only means that a real-only operation omitted nonzero imaginary data while complex mode was active. It can accompany a successfully computed real answer; it is not a save failure. Later input can remove the warning, so its absence does not certify that all stored inputs were real. See section 8.7.

LAST X and LAST Y can help after a successful but unintended RPN operation. They recall saved previous operands, distinct from the current X (S0) and Y (S1); recover them before another command overwrites the saved values. They do not provide a general error rollback or restore an earlier memory bank. Use the worked recovery sequence in section 3.8. If the original inputs are uncertain, record what remains, then re-enter a known problem rather than applying a series of guessed reversals.

14.9   Respond to a saved-state error

The messages in this section concern the local database, not the mathematical validity of a calculation. Record the full message before trying to continue. A long message can include a specific SQLite operation, error code, or state-validation detail that distinguishes an access problem from incompatible or damaged saved data.

Unable to save; the last saved state was restored

The application tried to save an action and could not finish the transaction. It then successfully reloaded the last durable calculator and presentation state. The attempted action has not been accepted as new saved work. The screen can return to an earlier entry or pending command, not merely an earlier displayed number.

For example, if the saved state was 42 followed by STO, and selecting R3 could not be saved, the restored state can again show the editable 42 and the pending STO. The register selection has not completed. Read those restored flags before deciding whether to retry the selector or cancel storage; typing a new calculation immediately could instead complete the pending command.

Check any cause identified by the message, such as an unavailable or unwritable storage location, and resolve that condition before relying on another save. After it is resolved, retry the intended action from the state actually restored. There is no separate Retry button. If the message recurs, stop making changes, record the failure and visible state, and report it. Repeated clears are also writes and do not repair a database access problem.

Restore failure or unavailable calculator memory

The message Unable to restore calculator memory appears when startup cannot open or reconstruct the saved calculator. Calculator memory is unavailable can appear when an unsuccessful save is followed by an unsuccessful attempt to reload it. The application disables calculator keys instead of silently replacing the saved database with a blank one. A zero or an older number still visible on the screen is not proof that the saved banks are empty or usable.

There is no editable recovery workspace, database-repair control, or factory-reset button in this screen. Record the full message and the application version, then obtain help with that particular storage failure. If the message says that the state was saved by a newer application, use the compatible build that created it rather than assuming that an older binary can read it. Reopening can retry startup, but cannot by itself repair invalid data or make an incompatible format compatible.

Preserve the affected installation’s data while investigating. Deleting the application data, removing its database, or creating a replacement database discards the saved work; those actions are not the same as canceling an entry and are not a recovery procedure supplied by this interface. Do not treat reinstalling as an assured way to preserve or repair calculator memory.

Information for a source-build investigation

The normal database is Calculator.sqlite in the application’s SpicyRPN directory under Application Support, within its sandbox. The exact enclosing path depends on the platform and installation; it is not a document you select from the calculator. The application uses SQLite’s WAL journal mode with synchronous FULL for its saves. A developer investigating a copy must preserve the database and any associated WAL state consistently; copying only an arbitrary live main file is not an application backup command.

Xcode previews and builds launched with the developer’s ephemeral option intentionally use in-memory state and do not retain it across process termination. Relaunch tests can use a separate temporary test database. If work seems to vanish only in a development or test run, include the launch configuration in the report. See chapter D for the supported build and test procedures.

14.10   Identify the build and report a reproducible problem

This manual identifies application version 2.0.0 (build 3). Open HELP, choose Licenses & Acknowledgments, then Credits to read the installed version and build. For a source build, the app target records MARKETING_VERSION and CURRENT_PROJECT_VERSION; the generated bundle records CFBundleShortVersionString and CFBundleVersion. Also record the source package version and any local changes when reporting a problem with your own build.

A useful report gives a short sequence that another person can follow without inheriting your current calculator. Include:

• Application version and build; source package version and local changes, if applicable; device or Mac model and OS version; screen orientation or window size.
• RPN or ALG; real or complex mode and representation; working and display digits; notation, angle unit, stack depth, date order, and payment timing wherever they affect the example.
• A complete preparation: which workspace or bank was cleared, which memory values or financial inputs were stored, and whether any entry, shift, or prefix was active.
• The exact key sequence, including shifts, panel changes, tool or worksheet field names and values, and the Apply, ENTER, COMPUTE, Use value, Close, or CANCEL action. Identify physical shortcuts when those were used instead of on-screen keys.
• The expected value or behavior and its basis, the actual result with exponent and relevant flags, and the first differing step. Include the whole error or warning text.
• Whether it repeats from that preparation and whether reopening changes it. For a persistence problem, identify the final successful action, the failing action, and what returned after relaunch.

A screenshot can document a layout defect or exact flag arrangement, but it does not show every hidden register or undisplayed digit. Include the relevant input values and the sequence in text as well. For financial work, state the period and rate conventions; for dates, write the intended calendar dates alongside their numeric encodings. For a numerical comparison, distinguish a difference in rounded output from a difference in retained value or algorithm.

If the report requires sensitive amounts, replace them with a small reproducible example when possible. A saved database can contain both current values and their calculation provenance, so do not assume it is equivalent to a screenshot of the display. Use the project’s report channel with the information needed to reproduce the problem, and retain the original data separately while the issue is investigated.