Add a compact format of scientific notation (new symbol, not a regular 'e')

[IKupriyanov-HORIS]

1*10^0 -> 1
1*10^1 -> 10
1*10^2 -> 10^2

[alshan]

We can cover (1) and (2) by adding settings similar to powerlimits in Matplotlib (and not just powers of 10 in this case).

As for (3), we can support 3rd option for the exponent_format parameter in theme:

• 'e' - regular "e" notation
• 'pow' - compact superscript
• 'pow_full' - superscript without shortening

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If, in addition to str, the exponent_format parameter could accept a tuple/array : (format, min_exp, max_exp), that would work IMO.

[alshan]

Added in v4.5.0