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Formatting Functions

Functions for formatting values for display. These functions are primarily available in dashboard expressions.

info

Formatting functions are available in frontend expressions (dashboards, displays) but not in server-side calculated attributes.

Common Patterns

  • Display Dates:

    formatDate(StartTime, "yyyy-MM-dd")         // 2024-03-15
formatDate(StartTime, "MMM d, yyyy")        // Mar 15, 2024
formatDate(StartTime, "HH:mm:ss")           // 14:30:45
formatDate(StartTime, "EEEE, MMMM d")       // Friday, March 15

  • Format Duration:

    formatDuration(3600000)                     // "1 h"
formatDuration(90000, "s")                  // "90 s"
formatDuration(86400000, "d")               // "1 d"

  • Display Percentages:

    formatPercentage(0.75)                      // "75%"
formatPercentage(0.333)                     // "33.3%"

Date Format Patterns

Uses date-fns format patterns. Common format tokens for formatDate:

  • Year:

    yyyy   4-digit year      2024
yy     2-digit year      24

  • Month:

    MM     Month (2 digits)  03
MMM    Month (short)     Mar
MMMM   Month (full)      March

  • Day:

    dd     Day (2 digits)    15
d      Day               15
EEEE   Day name (full)   Friday
EEE    Day name (short)  Fri

  • Time:

    HH     Hour (24h)        14
hh     Hour (12h)        02
mm     Minutes           30
ss     Seconds           45
a      AM/PM             PM

Duration Units

Available in frontend expressions only. Uses short unit labels:

ms     Milliseconds
s      Seconds
m      Minutes
h      Hours
d      Days
mo     Months
y      Years

formatDate

(timestamp, format)

Formats a timestamp using a date format pattern.

Parameters
timestamp number The timestamp to format
format string The format pattern, for example, 'yyyy-MM-dd' or 'HH:mm'
Returns string
Examples
formatDate(StartTime, "yyyy-MM-dd") → 2024-03-18
formatDate(StartTime, "HH:mm") → 14:30
Notes

Supported tokens are derived consistently for frontend and Athena: yyyy, MM, dd, HH, mm, ss, with M, d, H, m, s and MMM, MMMM, EEE, EEEE also supported for formatting. Formatting uses UTC semantics.

formatDuration

(duration, unit?)

Formats a duration in milliseconds as a human-readable string.

Parameters
duration number Duration in milliseconds
unit (optional) string Display unit: 'ms', 's', 'm', 'h', 'd', 'mo', 'y'
Returns string
Examples
formatDuration(3600000) → 1 h
formatDuration(90000, "s") → 90 s
Notes

Available in frontend expressions only. Uses short unit labels (s, m, h, d, mo, y).

formatPercentage

(value)

Formats a decimal value as a percentage.

Parameters
value number The decimal value (0.5 = 50%)
Returns string
Examples
formatPercentage(0.75) → 75%
formatPercentage(1.5) → 150%
Notes

Available in frontend expressions only.

formatNumber

(value, decimals?)

Formats a number with optional decimal places. Frontend only.

Parameters
value number The number to format
decimals (optional) number Number of decimal places
Returns string
Examples
formatNumber(1234.5, 2) → 1,234.50
Notes

Available in frontend expressions only.

formatCurrency

(value, currency, decimals?)

Formats a number as currency. Frontend only.

Parameters
value number The number to format
currency string ISO 4217 currency code, for example, EUR or USD
decimals (optional) number Number of decimal places
Returns string
Examples
formatCurrency(99.9, "EUR") → €99.90
Notes

Available in frontend expressions only.

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