TAN in SoftMaker PlanMaker 2026: examples and troubleshooting

For a right triangle, tangent is opposite side ÷ adjacent side. Its argument is an angle in radians, not a triangle side length and not a degree measure. In a quadrant where cosine is nonzero, the mathematical identity is tan(θ) = sin(θ)/cos(θ). Tangent repeats every π radians (180°), and is undefined at exact odd multiples of π/2. A computer uses approximate numbers, so near these angles the result can be very large rather than an explicit infinite value.

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.

=TAN(Number)

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 TAN; 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).

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.

Enter the column headings in A1:C1, the numeric inputs in A2:A7, and the indicated formulas in the same row. You can type =TAN(RADIANS(A2)) directly into C2 without column B, but keeping the conversion visible helps catch degree/radian mistakes. For rows 4, 6 and 7 allow normal floating-point tolerance; e.g., a displayed 0.9999999999999999 still represents the expected result of approximately 1.

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 TAN; output values other than the vendor’s explicit example were mathematically calculated independently.

• =TAN(RADIANS(30)) → independently expected 0.57735026919 (independently computed mathematical expectation, not a PlanMaker runtime test).
• =TAN(PI()/4) → independently expected 1 (independently computed mathematical expectation, not a PlanMaker runtime test).
• =TAN(-PI()/4) → independently expected -1 (independently computed mathematical expectation, not a PlanMaker runtime test).

Height from an elevation angle

Suppose a survey station is 20 metres horizontally from a wall and the elevation angle to its top is 30°. Put 20 in D2 and 30 in E2. In F2 enter:

=D2*TAN(RADIANS(E2))

Independently expected height above the instrument: 20 × tan(π/6) = 11.5470053838 m. This is only the vertical rise above the observer. Add instrument/eye height separately if you need total wall height; it is not included automatically.

A slope expressed as rise per unit run

Put 7 (rise) in D4 and 10 (horizontal run) in E4. =D4/E4 equals 0.7, a slope ratio. To calculate this ratio from the measured slope angle 34.9920201986° use =TAN(RADIANS(34.9920201986)), which independently approximates 0.7. Do not confuse the ratio 0.7 with 0.7 degrees or 70 degrees.

Avoid dividing by an almost-zero cosine

Mathematically, TAN(PI()/2) is undefined. Because PI() and arithmetic use finite precision, a worksheet may evaluate an approximation to a very large finite number rather than signal that the exact mathematical expression is undefined. Do not treat this as a trustworthy measurable slope. Flag inputs whose angle is very close to 90° + 180°×integer; consider whether the model itself has a vertical line rather than a finite slope.

Compare the ratio identity

For a well-conditioned angle such as 30°, =SIN(RADIANS(30))/COS(RADIANS(30)) has independently expected value 0.5773502692…, matching =TAN(RADIANS(30)) to normal numeric tolerance. The related SIN, COS, and RADIANS functions are documented by SoftMaker, though this comparison was not executed in PlanMaker.

TAN has one required numeric angle and no optional arguments or defaults. Exact behaviour for text booleans, blanks, precision at discontinuities, and platform-specific error rendering was not tested. The official function page gives the radian requirement and examples, not a finite-precision guarantee. In particular, never describe tangent of 90° as a defined finite result.

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).

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.

• Official SoftMaker PlanMaker 2026 TAN reference — syntax, purpose, and the vendor’s worked example.
• Official SoftMaker PlanMaker 2024 TAN reference — separate version cross-check.
• Official PlanMaker 2026 RADIANS — convert degrees to radians — vendor documentation.
• Official PlanMaker 2026 SIN — sine — vendor documentation.
• Official PlanMaker 2026 COS — cosine — vendor documentation.
• Official PlanMaker 2026 PI — π constant — vendor documentation.
• Official PlanMaker 2026 ATAN2 — two-coordinate arctangent — vendor documentation.
• PlanMaker 2026 formula-entry help — entering and editing a formula.
• PlanMaker 2026 error-values help — PlanMaker-specific error categories.
• Microsoft Excel TAN reference — separate vendor’s function documentation.

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.