Calligra Sheets DAYNAME: Weekday Names, Locale and Examples

DAYNAME converts a weekday number into a localized weekday name. Its documented input is an integer from 1 to 7, and its result is text. In an English locale, =DAYNAME(1) has the expected result Monday; =DAYNAME(7) has the expected result Sunday. A complete date is not the intended direct input: first obtain its weekday number using WEEKDAY(date;2). [K1, K3, K4, K5]

Evidence scope: Target Calligra 26.08.2, released October 8, 2026; the C++ date/time module, function XML, Calligra localization wrapper, KDE handbook and Qt C++ locale documentation were inspected October 13, 2026. These are documentation/source-inferred expected outputs, not observations from a running Calligra spreadsheet. Native Calligra execution and screenshots were unavailable. [K1–K6]

=DAYNAME(weekday)

The official XML defines one integer parameter and a string return type. The release source registers DAYNAME as new Function("DAYNAME",func_dayname) with no alternate-name registration, but it does not explicitly call setParamCount(1); therefore the documented arity is one and no omitted-argument or extra-argument behavior is guaranteed from this registration. Do not use aliases or undocumented defaults. The one-argument function requires no delimiter. For nested functions, KDE’s English handbook uses semicolons between arguments, such as WEEKDAY(A2;2); the installed formula-entry locale might be configured differently. [K1–K3]

Locale nuance: The handbook explains that countries use different first days of the week, but the pinned Calligra implementation does not itself shift the weekday number by the locale’s first-day setting. It converts the argument with asInteger(), calls Calligra Localization::dayName(number), and returns the localized string. The actual Calligra wrapper calls Qt C++ QLocale::standaloneDayName(number, LongFormat). Qt C++ uses Monday=1, Tuesday=2, … Sunday=7, regardless of the locale’s calendar-week starting day. The spelling and grammatical standalone form depend on locale. This is a source-level conclusion, not a native multi-locale experiment. [K2–K4, Q1]

Open a blank worksheet, put Weekday index in A1, Name from DAYNAME in B1 and English reference in C1. Enter integers 1 through 7 in A2:A8. In B2 enter =DAYNAME(A2) and fill it down to B8. Compare against this English-locale expected-results table (do not interpret it as a screenshot or native-run log). [K1–K4, C1]

KDE explicitly documents Monday as an example for DAYNAME(1) when the week starts Monday. Qt’s 1–7 C++ mapping independently supports the full ordering. Validation method: comparison with official documentation and the pinned implementation, plus an independent Python Gregorian calendar lookup; native Calligra execution: NOT DONE. [K1, K4, Q1, C1]

To label dates for a staff rota, enter Date in E1, Weekday number in F1 and Weekday label in G1. In E2 enter a typed date formula, =DATE(2026;6;1). In F2 enter =WEEKDAY(E2;2); in G2 enter =DAYNAME(F2). The expected F2 result is 1, and expected G2 text is Monday (English locale). You can combine those two steps: =DAYNAME(WEEKDAY(E2;2)). The date’s weekday was independently checked using Python date(2026,6,1).weekday() == 0, not by executing Calligra. [K1, K5, C2]

Avoid a hidden off-by-one error. KDE documents WEEKDAY’s default method 1 as Sunday=1, Monday=2, whereas method 2 is Monday=1, … Sunday=7. Its default numbering is therefore not compatible with passing the result directly into the pinned DAYNAME numbering. For Monday 2026-06-01, =DAYNAME(WEEKDAY(E2)) is source-inferred to label Tuesday, not Monday. Specify ;2 explicitly. This distinction matters even inside the same software. [K1, K4, K5, C2]

Keep the original date as the data value; create a separate numeric sort key =WEEKDAY(E2;2) and a label =DAYNAME(WEEKDAY(E2;2)). Sort by the number, not the English weekday names (alphabetical labels would put Friday before Monday). For a Sunday-first presentation, arrange or remap your sort key as needed; do not assume switching the calendar’s displayed first weekday changes the Calligra-to-Qt 1–7 name mapping. In translated worksheets, weekday names may vary in spelling or grammar while the numeric key stays portable. [K1, K4, K5]

• A date passed instead of a weekday index. DAYNAME(E2) on a typed date is not the documented one-number use. Write DAYNAME(WEEKDAY(E2;2)) instead. Date serials may convert to numbers outside 1–7; no exact error text was observed. [K1, K3, K5]
• WEEKDAY default used accidentally. Its default Sunday=1 gives indices that disagree with the DAYNAME-to-Qt 1=Monday mapping. Set method 2, and test Monday and Sunday rows before deploying a staffing report. [K1, K4, K5]
• Zero, eight, negative and fractional inputs. Valid documented range is whole numbers 1–7. The code performs Calligra asInteger conversion and checks whether the returned string is null before returning a value error. Whether 0, 8, 2.7, a text cell, or a blank causes a particular error is not established by the published examples. Do not invent a #VALUE! display claim or rounding rule; verify natively for your installed build. [K1–K4]
• Missing or excess parameters. The XML specifies one parameter, but explicit setParamCount is absent from DAYNAME’s registration. Neither =DAYNAME() nor =DAYNAME(1;2) has a verified runtime outcome here; do not treat either as supported syntax. [K1–K3]
• Unexpected language / grammatical form. Output is localized standalone weekday text. If a workbook is switched to another language, an English comparison column may differ even when the numeric weekday is correct. Avoid English string comparison for program logic; compare numeric weekday indices instead. [K3, K4, Q1]
• Function not recognized after importing. Confirm you are in Calligra Sheets and that its date/time module exists in that package. Catalogue registration in the 26.08.2 source is evidence of shipped definitions, not proof of your installed runtime. [K2, K6]

Calligra Sheets: Use DAYNAME(1) for a weekday number, or DAYNAME(WEEKDAY(E2;2)) for a real date in E2. The integer-to-string conversion, source-backed 1–7 mapping and localization are Calligra-specific. [K1–K5]

Microsoft Excel: Do not assume the DAYNAME name exists or behaves identically there. Microsoft documents TEXT(TODAY(),"dddd, mmmm dd") for the full weekday in an Excel date, so the analogous Excel-only =TEXT(E2,"dddd") formats a date cell as its full weekday name. Excel’s comma delimiter here is a Microsoft example, not evidence of Calligra’s TEXT behavior. Avoid claiming syntax for LibreOffice, Google Sheets, or other vendors without independently checking their official functions. [M1]

The official Calligra DAYNAME entry covers its one-argument syntax and integer range. The WEEKDAY entry specifies methods 1–3 and demonstrates Monday-first method 2. Qt’s C++ locale API documents localized full weekday names. These external links were checked October 13, 2026. [K1, K5, Q1]

Testing limitation: Native workbook locale, import behavior and visible errors remain untested.