ATAN in SoftMaker PlanMaker 2026: examples and troubleshooting
Find principal arctangent angles, calculate a slope from rise and run, and distinguish ATAN from quadrant-aware ATAN2.
Verification status: Official documentation referenced; example outcomes independently reasoned or arithmetically checked where stated. Not executed in SoftMaker PlanMaker 2026. How formula examples are checked
Quick answer: ATAN returns the principal arctangent angle in radians for a numeric tangent ratio. For example, =DEGREES(ATAN(1)) has an independently expected result of 45°. The input is a ratio, not an angle given in degrees. The source for the PlanMaker-specific syntax is SoftMaker PlanMaker 2026 (checked 2026-10-13). Calculated results below are independent mathematical expectations, not screenshots or native PlanMaker output.
What ATAN does and when to use it
Arctangent reverses tangent on its principal branch. Mathematically ATAN(x) returns an angle strictly between −π/2 and π/2 for any finite real input. The tangent ratio can be rise/run when run is nonzero, but that ratio alone does not distinguish opposite compass directions or quadrants. SoftMaker documents ATAN(1)≈0.7854 rad (45°) and recommends DEGREES to display an angle in degrees.
Use this function when the quantity being calculated and its units match the mathematical role described. The PlanMaker 2026 function reference is the evidence for the function’s actual PlanMaker name, parameter meaning, and unit conventions. Worked applications are explicitly derived from mathematics; their numeric outputs have not been confirmed by launching PlanMaker.
Exact syntax, argument order, types and defaults
=ATAN(number)
| Position | Argument (official manual spelling) | Required? | Type and meaning |
|---|---|---|---|
| 1 | number |
Required | Any finite numeric tangent ratio, such as rise ÷ nonzero horizontal run, or a formula/cell returning one. |
No optional parameters and no defaults are documented. The capitalization of the displayed parameter name is not a second function or alias. The English manual lists the function as ATAN; there is no documented alternate English function name on the referenced 2026 or 2024 entry. Start spreadsheet formulas with =. English-language examples use decimal points; decimal separators and function-name translations should be checked in the target installation rather than assumed. As this function takes a single argument, the primary syntax uses no list-separator comma or semicolon. The formula-entry instructions explain using the function dialog to check a local installation. PlanMaker 2026; PlanMaker 2024 (checked 2026-10-13).
Reproducible worksheet: input, formulas and expected results
Start a blank worksheet. Put each number in column A of the matching row, then enter the B and C formulas as shown. The final column below is an independently computed comparison, not a value read from PlanMaker.
| Row | A: tangent ratio (enter as a number) | B: arctangent in radians | C: angle in degrees | Independently expected C |
|---|---|---|---|---|
| 2 | -1 | =ATAN(A2) |
=DEGREES(B2) |
-45 |
| 3 | -0.5 | =ATAN(A3) |
=DEGREES(B3) |
approximately -26.56505118 |
| 4 | 0 | =ATAN(A4) |
=DEGREES(B4) |
0 |
| 5 | 0.5 | =ATAN(A5) |
=DEGREES(B5) |
approximately 26.56505118 |
| 6 | 1 | =ATAN(A6) |
=DEGREES(B6) |
45 |
| 7 | 1.7320508075688772 | =ATAN(A7) |
=DEGREES(B7) |
approximately 60 |
Enter headings in row 1, numeric tangent ratios in A2:A7, and formulas in B2:B7 and C2:C7. Do not type a percent-formatted cell unless you intend a percentage ratio: 50% means 0.5. If the goal is degrees, use column C; the raw ATAN result in B is radians.
How to verify: type the inputs as numbers, enter formulas with =, and compare the displayed values with the expectations at sensible precision. Different display formats and finite-precision arithmetic can change the final decimal places. Numeric display formatting does not change whether an angle is radians or degrees. The source formulas and output-unit requirement are documented by SoftMaker ATAN; output values other than the vendor’s explicit example were mathematically calculated independently.
Additional single-cell checks
=ATAN(1)→ independently expected 0.785398163397 (independently computed mathematical expectation, not a PlanMaker runtime test).=ATAN(-0.5)→ independently expected -0.463647609001 (independently computed mathematical expectation, not a PlanMaker runtime test).=DEGREES(ATAN(3/4))→ independently expected 36.8698976458 (independently computed mathematical expectation, not a PlanMaker runtime test).
Advanced use and common misconceptions
Find a ramp slope angle from horizontal measurements
Place 3 metres of rise in E2 and 4 metres of horizontal run in F2. Enter:
=DEGREES(ATAN(E2/F2))
Independently expected incline: atan(3/4) ≈ 36.8698976458°. The expression assumes F2 is nonzero and that the intended interpretation is the acute rise-over-run angle. A ramp’s diagonal surface length would require another setup.
Understand why a ratio does not identify quadrants
A point at (x=4,y=3) and a point at (x=-4,y=-3) have the same ratio y/x=0.75. Therefore ATAN(3/4) and ATAN(-3/-4) both return approximately 36.86989765° after DEGREES, but the second point lies in the third quadrant. A quadrant-aware formula is needed to identify its true direction; SoftMaker documents ATAN2(x,y) with two coordinates. Its argument order is explicitly x then y in PlanMaker 2026, so do not swap them based on familiarity with programming-language atan2(y,x) functions.
Check the inverse relation within the principal branch
=DEGREES(ATAN(TAN(RADIANS(30)))) independently returns 30°. At 150°, =DEGREES(ATAN(TAN(RADIANS(150)))) returns approximately −30°, because tangent is periodic and ATAN chooses the principal branch. It is therefore not a universal way to recover all signed bearings.
Treat steep slopes carefully
When horizontal run gets very small, rise/run becomes large; the principal arctangent approaches ±90° but never reaches those endpoints for a finite input. For a truly vertical line, E2/F2 divides by zero if F2 is 0. That is a division-by-zero issue in the ratio, not a missing optional ATAN argument. Consider ATAN2 for robust coordinate geometry.
Errors, edge cases and troubleshooting
| Symptom | Cause or caution | Practical correction |
|---|---|---|
ATAN(45) returns an angle close to 90°, not 45° |
The input 45 was interpreted as a tangent ratio, not 45 degrees. | For a 45-degree target check =ATAN(1); for forward trigonometry use =TAN(RADIANS(45)). |
| Direction looks wrong for a point in quadrant II or III | ATAN cannot recover a quadrant from the ratio alone. | Read the ATAN2(x,y) vendor page and include coordinate signs. |
Formula =ATAN(E2/F2) gives #DIV/0! |
F2 is zero; PlanMaker documents division-by-zero errors. | Validate the horizontal run and avoid dividing by zero. |
| Output shows 0.785 instead of 45 | ATAN returns radians. | Wrap with DEGREES. |
#NULL! / #VALUE! |
Malformed formulas or unsuitable argument types are documented error categories. | Type a numeric value directly and confirm parentheses and function spelling. |
ATAN accepts one required numeric ratio and has no optional parameters/defaults. Its mathematical principal branch and lack of quadrant information are essential constraints. PlanMaker separately documents ATAN2(x,y) for coordinate angles. No native cross-platform coercion, exact error message, .xlsx round-trip or Excel-specific edge case has been tested.
PlanMaker’s official 2026 error-values guide identifies #NUM! as an invalid numerical input, #VALUE! as an inappropriate argument type, #NULL! as an invalid formula or function signature, and #DIV/0! as division by zero. These are general documented categories, not claims that each particular formula in this review was executed to observe a particular error display. Never copy an Excel-specific error code into a PlanMaker guide without checking the vendor documentation first. (PlanMaker error values, checked 2026-10-13).
PlanMaker release, platform, localization and Microsoft Excel compatibility
| Environment | What is actually supported by evidence | Validation limitation |
|---|---|---|
| PlanMaker 2026 / NX English reference | Lists ATAN(number) and the function meaning described above. 2026 manual. |
Documentation only. No PlanMaker 2026 or NX execution performed. |
| PlanMaker 2024 English reference | Lists the same function name, one-argument order and general mathematical purpose. 2024 manual. | No PlanMaker 2024 execution performed; historical feature-availability should not be extrapolated to all earlier products. |
| Windows / macOS / Linux editions | SoftMaker markets Office Professional 2026 for Windows, Mac and Linux, and NX in multiple platform families. SoftMaker product site. | Marketing and the shared manual do not certify this exact function across every installed build, license, OS or regional configuration. |
| iOS / Android / FreeOffice | The product family may include mobile offerings, but no per-device ATAN feature verification was performed. | Not asserted supported or unsupported. Verify locally or in the edition-specific help. |
| Locale and formula input | The English manual uses the English name ATAN and one argument. Function entry. |
Localized names, decimal-comma locales and any relevant separators not tested. Read the installed function dialog. |
| Microsoft Excel (independently documented) | Microsoft’s separate =ATAN(number)-family function reference documents the corresponding mathematical operation and radian/ratio convention. Excel ATAN. |
A documented mathematical/syntax match is not a tested Excel import/export round-trip or a claim that every edge-case error is identical. |
For .xlsx interchange, compare results on representative numeric inputs in both applications before treating a production workbook as validated. No workbook was opened, converted, saved, or executed in either PlanMaker or Excel during this research run.
Checked related documentation
- Official SoftMaker PlanMaker 2026 ATAN reference — syntax, purpose, and the vendor’s worked example.
- Official SoftMaker PlanMaker 2024 ATAN reference — separate version cross-check.
- Official PlanMaker 2026 ATAN2 — two-coordinate arctangent — vendor documentation.
- Official PlanMaker 2026 DEGREES — convert radians to degrees — vendor documentation.
- Official PlanMaker 2026 RADIANS — convert degrees to radians — vendor documentation.
- Official PlanMaker 2026 PI — π constant — vendor documentation.
- Official PlanMaker 2026 SIN — sine — vendor documentation.
- PlanMaker 2026 formula-entry help — entering and editing a formula.
- PlanMaker 2026 error-values help — PlanMaker-specific error categories.
- Microsoft Excel ATAN reference — separate vendor’s function documentation.
Source and testing disclosure
Reference-check date: 2026-10-13. PlanMaker 2026 and PlanMaker 2024 function pages were reviewed separately, as were the current SoftMaker general help pages and the Microsoft Excel reference. All example values are independently calculated, using elementary mathematical identities and Python’s math routines as appropriate. This is not a native SoftMaker result.
Validation matrix: PlanMaker 2026: 0 native formula executions; PlanMaker 2024: 0; PlanMaker NX: 0; Excel: 0; other editions/platforms: 0; screenshots: 0; Excel import/export checks: 0.