Formatting Axis in Visualizations

Visualizations X and Y axis values are formatted with D3. Below you can find examples for the various format options.

Numbers

The general form of a number specification is:

[​[fill]align][sign][symbol][0][width][,][.precision][~][type]

fill can be any character. The presence of a fill character is signaled by the align character following it, which must be one of the following:

• > - Forces the field to be right-aligned within the available space. (Default behavior).
• < - Forces the field to be left-aligned within the available space.
• ^ - Forces the field to be centered within the available space.
• = - like >, but with any sign and symbol to the left of any padding.

sign can be:

• - - nothing for zero or positive and a minus sign for negative. (Default behavior.)
• + - a plus sign for zero or positive and a minus sign for negative.
• ( - nothing for zero or positive and parentheses for negative.
• (space) - a space for zero or positive and a minus sign for negative.

symbol can be:

• $ - apply currency symbols per the locale definition.
• # - for binary, octal, or hexadecimal notation, prefix by 0b, 0o, or 0x, respectively.

The zero (0) option enables zero-padding; this implicitly sets fill to 0 and align to =. The width defines the minimum field width; if not specified, then the width will be determined by the content. The comma (,) option enables the use of a group separator, such as a comma for thousands.

Depending on the type, the precision either indicates the number of digits that follow the decimal point (types f and %), or the number of significant digits (types ​, e, g, r, s and p). If the precision is not specified, it defaults to 6 for all types except ​ (none), which defaults to 12. Precision is ignored for integer formats (types b, o, d, x, and X) and character data (type c).

The ~ option trims insignificant trailing zeros across all format types. This is most commonly used in conjunction with types r, e, s and %.

The available type values are:

• e - exponent notation.
• f - fixed point notation.
• g - either decimal or exponent notation, rounded to significant digits.
• r - decimal notation, rounded to significant digits.
• s - decimal notation with an “SI prefix” (k, M, G, …), rounded to significant digits.
• % - multiply by 100, and then decimal notation with a percent sign.
• p - multiply by 100, round to significant digits, and then decimal notation with a percent sign.
• b - binary notation, rounded to integer.
• o - octal notation, rounded to integer.
• d - decimal notation, rounded to integer.
• x - hexadecimal notation, using lower-case letters, rounded to integer.
• X - hexadecimal notation, using upper-case letters, rounded to integer.
• c - character data, for a string of text.

The type ​ (none) is also supported as shorthand for ~g (with a default precision of 12 instead of 6), and the type n is shorthand for ,g. For the g, n and ​ (none) types, decimal notation is used if the resulting string would have precision or fewer digits; otherwise, exponent notation is used. For example:

Time

The time format string may contain the following directives:

• %a - abbreviated weekday name.*
• %A - full weekday name.*
• %b - abbreviated month name.*
• %B - full month name.*
• %c - the locale’s date and time, such as %x, %X.*
• %d - zero-padded day of the month as a decimal number [01,31].
• %e - space-padded day of the month as a decimal number [ 1,31]; equivalent to %_d.
• %f - microseconds as a decimal number [000000, 999999].
• %g - ISO 8601 week-based year without century as a decimal number [00,99].
• %G - ISO 8601 week-based year with century as a decimal number.
• %H - hour (24-hour clock) as a decimal number [00,23].
• %I - hour (12-hour clock) as a decimal number [01,12].
• %j - day of the year as a decimal number [001,366].
• %m - month as a decimal number [01,12].
• %M - minute as a decimal number [00,59].
• %L - milliseconds as a decimal number [000, 999].
• %p - either AM or PM.*
• %q - quarter of the year as a decimal number [1,4].
• %Q - milliseconds since UNIX epoch.
• %s - seconds since UNIX epoch.
• %S - second as a decimal number [00,61].
• %u - Monday-based (ISO 8601) weekday as a decimal number [1,7].
• %U - Sunday-based week of the year as a decimal number [00,53].
• %V - ISO 8601 week of the year as a decimal number [01, 53].
• %w - Sunday-based weekday as a decimal number [0,6].
• %W - Monday-based week of the year as a decimal number [00,53].
• %x - the locale’s date, such as %-m/%-d/%Y.*
• %X - the locale’s time, such as %-I:%M:%S %p.*
• %y - year without century as a decimal number [00,99].
• %Y - year with century as a decimal number, such as 1999.
• %Z - time zone offset, such as -0700, -07:00, -07, or Z.
• %% - a literal percent sign (%).

Directives marked with an asterisk (*) may be affected by the locale definition.

The % sign indicating a directive may be immediately followed by a padding modifier:

• 0 - zero-padding
• _ - space-padding
• - - disable padding

If no padding modifier is specified, the default is 0 for all directives except %e, which defaults to _.