ISERROR in WPS Spreadsheet: Error Flags, Ratio Audits and Data-Quality Limits
Audit WPS calculations with ISERROR, retain error evidence beside results, and distinguish an error-free numeric result from a valid business observation.
Verification status: See the evidence and test scope described in this guide. How formula examples are checked
Quick answer: ISERROR(value) returns TRUE for an error value and FALSE otherwise. It detects an error; it does not repair it or determine whether an error-free number makes sense for the task. The official WPS lesson explicitly demonstrates this function in WPS 2019.
Availability and version history
- Introduced: documented by 2019-05-08 in official WPS material; original introduction is not established.
- Availability: The dedicated lesson explicitly demonstrates WPS 2019 and lists Windows Personal.
- Scope: exact current supported builds remain unverified; this evidence does not establish equivalent behavior across every WPS client.
- Checked: October 14, 2026 against complete function-specific documentation. Examples are independently modeled; no native WPS test was performed.
Syntax and first controls
=ISERROR(value)
=ISERROR(1/0)
=ISERROR(NA())
=ISERROR("#N/A")
The final three formulas have expected results TRUE, TRUE and FALSE. An actual #N/A error is included, while text spelling that label is not an actual error.
The argument can be a reference or an expression to evaluate. Examples use English function names and comma separators. Their outputs are independently modeled from the official definition, not native WPS execution records.
Example 1: audit a column of ratios
Enter this A1:B7 table. Put =A2/B2 in C2 and fill down; place the error flag =ISERROR(C2) in D2 and fill down.
| A · Amount | B · Units | Expected ratio | Expected error flag |
|---|---|---|---|
| 12 | 3 | 4 | FALSE |
| 15 | 0 | #DIV/0! | TRUE |
| 0 | 2 | 0 | FALSE |
| 9 | 0 | #DIV/0! | TRUE |
| 6 | 2 | 3 | FALSE |
| 8 | 4 | 2 | FALSE |
There are two calculation errors and four non-error results. The zero numerator with a nonzero denominator is a valid arithmetic result of zero, so it is not flagged.
Example 2: keep the diagnostic beside a presentation result
Put this in E2 and fill down:
=IF(ISERROR(C2),"Review calculation",C2)
Expected selected values are 4, Review calculation, 0, Review calculation, 3 and 2. Column C retains the actual results and errors; column E provides a readable presentation.
This avoids changing the original evidence just to make a report appear tidy. The selected-output model follows the documented IF pattern, without asserting that every nested failing expression is skipped in every client.
Advanced example: quantify coverage without changing the values
In F2 use =IF(D2,1,0) and fill through F7. The indicators 0, 1, 0, 1, 0 and 0 sum to 2. For the six controlled observations, the error proportion is 2/6, approximately 0.333333333.
The four known numeric ratios total 9, with average 9/4 = 2.25. Replacing the two errors with numeric zero and averaging all six rows instead gives 9/6 = 1.5. That lower result is caused by a different denominator policy, not an improvement in the data.
A coverage count helps explain which population a summary actually describes. It does not determine whether excluding or imputing a record is appropriate for a real analysis.
Advanced distinction: no error is not the same as valid data
For an already numeric control, =-9/3 returns -3, so ISERROR returns FALSE. If negative ratios are forbidden by the intended business rule, the observation still needs review even though the arithmetic succeeded.
Likewise, =ISERROR("Pending") returns FALSE. The input is text, not an error, but it is not a usable numeric measurement. Use ISNUMBER to ask the separate numeric-type question, then apply the relevant range or sign rule to validated numbers.
The WPS walkthrough informally describes a FALSE flag as showing that a journey calculation is “correct.” This guide limits that conclusion to the absence of a detected calculation error; it does not validate the realism or units of the underlying journey data.
Advanced check: split unavailable values from other errors
For three controls consisting of an actual #N/A, an actual #DIV/0! and the number 5:
| Test | #N/A | #DIV/0! | 5 |
|---|---|---|---|
| ISERROR | TRUE | TRUE | FALSE |
| ISNA | TRUE | FALSE | FALSE |
| ISERR | FALSE | TRUE | FALSE |
ISNA identifies the unavailable-value category. ISERR detects errors other than #N/A. This classification is useful when those groups require different follow-up rather than a single broad fallback.
Limits and troubleshooting
The examples do not enumerate every newer error category, array result or parse-time failure. An invalid formula may fail before ISERROR receives an evaluated argument. Check syntax and references separately.
Use IFERROR when replacing errors is an explicit reporting policy. Keep source values, error counts and the reason for any replacement visible so a clean-looking output is not mistaken for a fully validated dataset.
References and verification
- WPS Academy: ISERROR, 2019-05-08 (Chinese; edition scope as stated above).
- WPS Academy: shared IS-function syntax and nonconversion rule, May 14, 2019 (Windows Personal).
- Editorial testing standards.
The source establishes the cited product behavior and documented history, not a native-tested current release. Additional linked functions retain their own evidence scopes.