Point Notation

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Base Point Notation: e.g., 16b10FFFFas a shorthand for 16⊥1 0 15 15 15 15 15.
Euler Point Notation: e.g., 2x3 as a shorthand for 2e3 or 2×(*1)*3
Pi Point Notation: e.g., 2p3 as a shorthand for 3 or 2×(○1)*3
Decimal Point Notation: e.g., 2.5 as a shorthand for or 2+5÷10
Exponential Point Notation: e.g., 2e3 as a shorthand for 2•103 or 2×10*3
Base, Pi, and Euler Point Notations are extensions to the familiar Decimal Point Notation as well as Exponential Point or Scientific Notation methods of entering numeric constants. Thanks to the designers of J for this clever idea.


Base Point Notation

This notation makes it easy to enter numeric constants in an arbitrary base.

The number to the left of the b is the base of the number system for the characters to the right of the b. The base may be represented in several ways including integers, Exponential, Decimal, Pi, and Euler Point Notation, but not Base Point Notation.

For example, 1e3b111 is the same as 1000b111.

Note that the base may also be negative as in ¯1b0z or fractional as in 0.1b1234.

The characters to the right of the b may range from 0-9 or a-z where the latter range is a way of representing numbers from 10-35 in a single character. The uppercase letters (A-Z) have the same values as the corresponding lowercase case letters and may be used instead of or intermixed with them.

For example, 10bzzZ is the same as 10⊥35 35 35 35.

Euler Point Notation

This notation allows you to enter numeric constants that are in the form of the product of a multiplier and e (the base of the natural logarithms) raised to an exponent, that is, M×(*1)*E. The numbers to the left (multiplier) and right (exponent) of the x may be represented in several ways including integers, Decimal, or Exponential Point Notation, but not Base, Pi, or Euler Point Notation.

For example, 1e2x1.1 is the same as 100x1.1.

Both the multiplier and exponent may be negative and/or fractional as in ¯1e2x¯3.3.

Pi Point Notation

This notation allows you to enter numeric constants that are in the form of the product of a multiplier and π raised to an exponent, that is, M×(○1)*E. The numbers to the left (multiplier) and right (exponent) of the p may be represented in several ways including integers, Decimal, or Exponential Point Notation, but not Base, Euler, or Pi Point Notation.

For example, 1e2p1.1 is the same as 100p1.1.

Both the multiplier and exponent may be negative and/or fractional as in ¯1e2p¯3.3.