ATAN2 in Collabora Office: Preserve Quadrants with x-Then-y Coordinates
Calculate quadrant-aware direction in Collabora Office, including x-first argument order and the documented zero-origin behavior.
Verification status: See the evidence and test scope described in this guide. How formula examples are checked
Quick answer: ATAN2 returns the angle from the x-axis to a point given by its x coordinate first and y coordinate second. =DEGREES(ATAN2(3;4)) is expected to return approximately 53.130102354 degrees.
Availability and version history
- Introduced: documented in Collabora Office 26.04 Help; the original introduction version is not established by the reviewed history.
- Availability: the official ATAN2 reference documents support in Calc’s 26.04 desktop manual.
- Scope: this evidence does not establish identical behavior in Collabora Online, mobile clients or older releases.
- Checked: October 14, 2026 against the captured 26.04 manual. Examples were calculated independently; no native Collabora execution was performed.
Syntax and the argument-order trap
=ATAN2(number_x; number_y)
The official Collabora 26.04 help explicitly identifies this x-then-y order and warns that programming languages commonly reverse it. Python’s atan2(y,x), for example, is not a literal argument-order template for a Calc formula.
The result is an angle in radians. Wrap it in DEGREES for degree output. The coordinates should describe the same origin and scale; swapping them can yield a different direction even when no formula error appears.
Example 1: compare all four quadrants
Enter the following pairs in A2:B5 and use =DEGREES(ATAN2(A2;B2)) in C2, then fill down:
| A: x | B: y | Expected degrees |
|---|---|---|
| 4 | 4 | 45 |
| −4 | 4 | 135 |
| −4 | −4 | −135 |
| 4 | −4 | −45 |
The coordinates have the same absolute magnitudes but different signs. Keeping x and y separate lets ATAN2 distinguish these directions; ATAN(y/x) would collapse some of them to the same ratio.
A negative angle expresses a clockwise direction from the positive x-axis in these examples. It is another representation of a direction that can also be expressed using a nonnegative full-turn convention.
Example 2: test the coordinate axes
=DEGREES(ATAN2(5;0))
=DEGREES(ATAN2(0;5))
=DEGREES(ATAN2(0;-5))
Expected results: approximately 0, 90, −90 degrees. There is no y/x division in these formulas, so a zero x coordinate does not create a division-by-zero step.
Use an axis test when translating formulas from code. If the point (0,5) produces an angle near zero, the arguments were probably swapped.
Important Collabora-specific origin behavior
=ATAN2(0;0)
The official 26.04 help documents a result of 0 in Collabora Office. Do not replace this with an error rule copied from another spreadsheet.
Mathematically, the zero vector has no direction. The documented return value is an application convention, not evidence of a meaningful zero-degree direction. If direction is required by your model, explicitly flag the zero-vector case instead of accepting that numeric convention as a measurement.
For numeric coordinates in A2 and B2:
=IF(AND(A2=0;B2=0);"No direction";DEGREES(ATAN2(A2;B2)))
Expected result for (0,0): No direction. For (3,4), the expected result is approximately 53.130102354 degrees.
Advanced example: convert a signed angle to a full-turn label
If the chosen display convention is from 0 up to 360 degrees:
=MOD(DEGREES(ATAN2(-4;-4));360)
Expected result: approximately 225 degrees. The signed result −135 and the full-turn label 225 describe the same direction. This is a deliberate presentation convention, not a change to the coordinate system.
Use the same convention across a report, especially before comparing angles near the full-turn boundary. Angles 359 and 1 degrees are close directions despite their ordinary numeric difference.
Advanced example: recover the coordinates
For the point (3,4), the radius is =SQRT(3^2+4^2), expected 5. In E2 put that radius; in F2 enter =ATAN2(3;4) to keep the angle in radians. Then:
=E2*COS(F2)
=E2*SIN(F2)
Expected results: approximately 3 and 4. The COS and SIN functions take radians, so no extra conversion belongs in those two formulas.
If F2 instead stores degrees, convert it with RADIANS before using SIN or COS. Mixing an angular display unit with the input expected by the next function is a common silent error.
Precision and verification
Check all four quadrants, a zero-x axis case and the origin convention. These cover distinct behaviors that one positive coordinate pair cannot validate. The numeric examples were independently calculated; the origin value comes directly from the Collabora manual and is not a new native observation.
Use a tolerance for reconstructed coordinates because trigonometric calculations are approximate. Confirm how a receiving program handles the origin and the negative-x boundary before moving an angle-dependent workbook across products.
References and verification
- Collabora Office 26.04 Help: ATAN2 — direct product-specific definition and syntax.
- Editorial testing standards.
The examples use semicolon argument separators. Displayed decimals are rounded expected values, not exact native outputs. Mathematical identities are explanatory calculations; product support is limited to the cited documentation scope.