Dataskera

Calendar

The Calendar reads a measure day by day, at three zoom levels: a year of weeks for seasonality, the month page everyone knows how to read, a week strip for operations. Its one discipline is small and strict: a day with no data is visibly empty and a day at zero sits on the scale, because null is not zero.

Data Requirements

Your Tableau worksheet should include:

  • 1 Date dimension for the Date encoding. One cell per day. Finer-grained data is aggregated to the day.
  • 1 Measure for the Value encoding. Drives the cell color and the number in the cell.
  • 1 Measure, optional for the Secondary encoding. A second number per day, as a sub-label or a marker dot.

Add Calendar to your worksheet

First, download the manifest file. It tells Tableau where to load the extension from.

Download calendar.trex

Direct link: https://dataskera.com/downloads/calendar.trex

Then, in Tableau:

  1. On the Marks card, open the Mark type dropdown, and under Viz Extensions choose Add Extension.
  2. In the Add an Extension dialog, choose Access Local Viz Extensions, then open the calendar.trex file you just downloaded.
  3. When Tableau asks, allow the extension to access the data in the workbook.
  4. The welcome screen appears. Sign in with your Dataskera account, or on Tableau Desktop choose Use on Desktop without an account. See Signing in & access below.
  5. Build the chart: drag a date dimension at day level onto Date and a measure onto Value.
Tableau Server or Cloud:
A site admin must allow the extension by adding its URL to the site's safe list, and the view needs the Download Summary Data permission. Extension URL: https://vizextension.dataskera.com/calendar/calendar.html

Signing in & access

Calendar is free. Whether you need to sign in depends only on what you are doing. Viewing a dashboard never asks for an account, and authoring is free too.

Viewing a dashboard
No account

People who only view a dashboard are never asked to sign in and are never blocked.

Editing on Tableau Desktop
Optional

Sign in, or continue without an account in a single click.

Editing on Server or Cloud
Free account

Sign in with your Dataskera account to author on the web.

No account yet? Create one free in under a minute. No credit card required.

Format panel

Open the Format panel from the extension menu to customize the chart. It is for the dashboard author and is not shown to viewers. It has four tabs:

  • Calendar: year, month or week view, the day the week starts on, weekend shading, the outline on today.
  • Cells: color, value or both in each cell, how an empty day is drawn, how the secondary measure appears, the below-zero color, cell spacing, number format and font.
  • Color: a palette, a precise colour per category, and the overall opacity.
  • Legend: show or hide it, its position around the chart, an optional show/hide toggle for viewers, the colour swatch, and the content of each entry.
  • Tooltip: show or hide it, its colours, decimals, and a template you write yourself from the placeholders the chart provides.
Null is not zero:
A day with no row renders as an empty outlined cell, distinct in the legend; a day whose value is zero is filled at the zero end of the scale. Folding the two together is how calendars quietly lie.
Dates without surprises:
Day keys come from the date value's own parts, never from parsing a formatted string, so the chart cannot drift by one day across locales and timezones.
Mixed signs:
When the data carries both gains and losses, the scale becomes diverging around zero, with the negative side on its own color. A sequential ramp over mixed signs would paint a small loss and a small gain the same.
Averages per day:
AVG, MEDIAN and COUNTD cannot be rebuilt from summary rows when several rows share a day. The chart says so instead of printing a plausible wrong number; use SUM or data already at one row per day.