vals.fmt_scientific

vals.fmt_scientific(x, decimals=2, n_sigfig=None, drop_trailing_zeros=False, drop_trailing_dec_mark=True, scale_by=1, exp_style='x10n', pattern='{x}', sep_mark=',', dec_mark='.', force_sign_m=False, force_sign_n=False, locale=None)

Format values to scientific notation.

With numeric values in a list, we can perform formatting so that the input values are rendered in scientific notation, where extremely large or very small numbers can be expressed in a more practical fashion. Here, numbers are written in the form of a mantissa (m) and an exponent (n) with the construction m x 10^n or mEn. The mantissa component is a number between 1 and 10. For instance, 2.5 x 10^9 can be used to represent the value 2,500,000,000 in scientific notation. In a similar way, 0.00000012 can be expressed as 1.2 x 10^-7. Due to its ability to describe numbers more succinctly and its ease of calculation, scientific notation is widely employed in scientific and technical domains.

We have fine control over the formatting task, with the following options:

• decimals: choice of the number of decimal places, option to drop trailing zeros, and a choice of the decimal symbol
• scaling: we can choose to scale targeted values by a multiplier value
• pattern: option to use a text pattern for decoration of the formatted values
• locale-based formatting: providing a locale ID will result in formatting specific to the chosen locale

Parameters

Name	Type	Description	Default
x	X	A list of values to be formatted.	required
decimals	int	The decimals values corresponds to the exact number of decimal places to use. A value such as 2.34 can, for example, be formatted with 0 decimal places and it would result in "2". With 4 decimal places, the formatted value becomes "2.3400". The trailing zeros can be removed with drop_trailing_zeros=True.	2
n_sigfig	int | None	A option to format numbers to n significant figures. By default, this is None and thus number values will be formatted according to the number of decimal places set via decimals. If opting to format according to the rules of significant figures, n_sigfig must be a number greater than or equal to 1. Any values passed to the decimals and drop_trailing_zeros arguments will be ignored.	None
drop_trailing_zeros	bool	A boolean value that allows for removal of trailing zeros (those redundant zeros after the decimal mark).	False
drop_trailing_dec_mark	bool	A boolean value that determines whether decimal marks should always appear even if there are no decimal digits to display after formatting (e.g., 23 becomes 23. if False). By default trailing decimal marks are not shown.	True
scale_by	float	All numeric values will be multiplied by the scale_by value before undergoing formatting. Since the default value is 1, no values will be changed unless a different multiplier value is supplied.	1
exp_style	str	Style of formatting to use for the scientific notation formatting. By default this is "x10n" but other options include using a single letter (e.g., "e", "E", etc.), a letter followed by a "1" to signal a minimum digit width of one, or "low-ten" for using a stylized "10" marker.	'x10n'
pattern	str	A formatting pattern that allows for decoration of the formatted value. The formatted value is represented by the {x} (which can be used multiple times, if needed) and all other characters will be interpreted as string literals.	'{x}'
sep_mark	str	The string to use as a separator between groups of digits. For example, using sep_mark="," with a value of 1000 would result in a formatted value of "1,000". This argument is ignored if a locale is supplied (i.e., is not None).	','
dec_mark	str	The string to be used as the decimal mark. For example, using dec_mark="," with the value 0.152 would result in a formatted value of "0,152"). This argument is ignored if a locale is supplied (i.e., is not None).	'.'
force_sign_m	bool	Should the plus sign be shown for positive values of the mantissa (first component)? This would effectively show a sign for all values except zero on the first numeric component of the notation. If so, use True (the default for this is False), where only negative numbers will display a sign.	False
force_sign_n	bool	Should the plus sign be shown for positive values of the exponent (second component)? This would effectively show a sign for all values except zero on the second numeric component of the notation. If so, use True (the default for this is False), where only negative numbers will display a sign.	False
locale	str | None	An optional locale identifier that can be used for formatting values according the locale’s rules. Examples include "en" for English (United States) and "fr" for French (France).	None

Returns

Type	Description
list[str]	A list of formatted values is returned.