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Types

Each value on the calculator stack is a string of bytes. When an operation needs to pop a value off the stack, it must first parse the value into the desired type. Results are then formatted to a string before being pushed back onto the stack.

Each type has a function for parsing and formatting. A value is considered to be of a type if it can be successfully parsed by that type's parse function. The parse function for a floating point number can parse values such as 6, 6.4, 6e4 but not '6 2/5' which requires a conversion function.

Table of contents:

Bool

A Boolean is a value that is either true or false.

An item on the stack can be parsed as a boolean if it is equal to true or false when all characters are converted to lowercase. Operations are defined for true and false that simply return that string.

Example:

Input Stack
true true and true
'FALSE' and false
1 and no operation for: 'false' 1 and

Complex

A Complex value is a number that has a floating point real number, real, and a floating point imaginary number, imag in the form of real+imagi.

Input Stack
-16 sqrt 0+4i
2+2i add 2+6i

DateTime

Parsing of DateTime values tries to be as lenient as possible to allow easy entry by hand or from various sources via cut and paste. Parsing uses the following rules:

  • If a date and time is needed but the value only contains a time, the date portion is set to today's date.
  • Days of week such as Monday are parsed but ignored. The day of week is computed from the actual date.
  • If a two digit year is used it is assumed to apply to the current century. The value of 23 is set to the year 2023 and the value of 99 is set to 2099. Use a four digit year to use 1999.

The types of Date and Time are used when only those portions of a DateTime are necessary.

All of the following formats can be parsed:

Input Stack
c 2006-01 dt Sun Jan 1 2006 12:00:00am -0700 MST
c 2006-01-02 dt Mon Jan 2 2006 12:00:00am -0700 MST
c 2006-032 dt Wed Feb 1 2006 12:00:00am -0700 MST
c 1/2 dt Mon Jan 2 2006 12:00:00am -0700 MST
c 1/2/2006 dt Mon Jan 2 2006 12:00:00am -0700 MST
c 1/2/06 dt Mon Jan 2 2006 12:00:00am -0700 MST
c 'Jan 2 2006' dt Mon Jan 2 2006 12:00:00am -0700 MST
c 'Jan 2 06' dt Mon Jan 2 2006 12:00:00am -0700 MST
c 'Fri Jan 2 2006' dt Mon Jan 2 2006 12:00:00am -0700 MST
c 'Friday Jan 2 2006' dt Mon Jan 2 2006 12:00:00am -0700 MST
c 'Jan 2' dt Mon Jan 2 2006 12:00:00am -0700 MST
c 'Fri, Jan 2' dt Mon Jan 2 2006 12:00:00am -0700 MST
c 15:04:05 dt Mon Jan 2 2006 3:04:05pm -0700 MST
c '15:04:05 PDT' dt Mon Jan 2 2006 3:04:05pm -0700 PDT
c 15:04 dt Mon Jan 2 2006 3:04:00pm -0700 MST
c 3:04PM dt Mon Jan 2 2006 3:04:00pm -0700 MST
c '3:04 PM' dt Mon Jan 2 2006 3:04:00pm -0700 MST
c 3:04a dt Mon Jan 2 2006 3:04:00am -0700 MST
c '3:04a EST' dt Mon Jan 2 2006 3:04:00am -0500 EST
c '3:04a -0500' dt Mon Jan 2 2006 3:04:00am -0500
c '3:04a EST -0500' dt Mon Jan 2 2006 3:04:00am -0500 EST

The examples above are the result if the current time is Jan 2 2006 15:04:05 -0700 MST.

Decimal

A Decimal value is a number using fixed-point math and support is provided by the shopspring/decimal library. The calculator prefers working with Decimal values whenever an operation can use a function in this library.

Decimal values first remove formatting characters. By default, values containing exponent notation are not parsed as a decimal. To parse as a decimal, add a d suffix to the number. Example:

Input Stack
c 1e10 1e10 add 2e10
c 1e10d 1e10d add 20000000000

DMS

A DMS value is an angle that can be expressed as:

  • decimal degrees
  • degrees and minutes
  • degrees, minutes, and seconds

Any valid decimal number, such as 12.345 can be parsed as a DMS value. Use unit markers to designate each part of the DMS by using:

  • degrees: d, °
  • minutes: m, ', ′
  • seconds: s, ", ″

Using the letter unit markers with no whitespace is the easiest to use when entering values manually. All of the following parse to the same value:

Input Stack
c 10.5125 dec 10.5125
c 10.5125d dec 10.5125
c 10.5125° dec 10.5125
c 10d30.75m dec 10.5125
c 10d30.75' dec 10.5125
c [10° 30′ 45″] dec 10.5125

Duration

A Duration is a value with hours, minutes, and seconds in the form of hourshminutesmsecondss. Zero values may be omitted. Examples:

Input Stack
4h15m30s 10m20s add 4h 25m 50s
10s add 4h 26m
34m add 5h

Float

A Float value is a number using floating-point math. For operations supported by Decimal, those are preferred over using a Float. To force the use of a float, add a f suffix to the number.

Input Stack
c 1.1 2.2 add 3.3
c 1.1f 2.2f add 3.3000000000000003

Float values first remove formatting characters when parsing. Exponents can follow a number using an e, or a ×10. The latter form is useful in copy and paste operations (e.g., from Wikipedia).

Example:

3×102

Input Stack
c 3e2 2e1 add 320
c 3×102 2×101 add 320

Integer

An Integer value is a number that can either be a:

  • BigInt; or
  • Int, Int64, Int32, Int16, Int8; or
  • Uint, Uint64, Unit32, Uint16, Uint8

A BigInt is an integer of an arbitrary size and support is provided by the math/big library. The calculator prefers working with BigInt values whenever an operation can use a function in this library.

The Int and Uint series of types are signed and unsigned integers of a specific size and are used when an underlying implementation of an operation needs that type.

Integer values first remove formatting characters when parsing. Integers may have a radix prefix of:

  • 0b: binary number, base 2
  • 0o: octal number, base 8
  • 0x: hexadecimal number, base 16
Input Stack
c 0b11111111 dec 255
c 0o377 dec 255
c 0xff dec 255

Rational

A Rationalvalue is a number that has a numerator n and a denominator d in the form of n/d. A whole number can prefix a rational using a , _ or - character. Examples:

Input Stack
c 1/2 1/4 add 3/4
c 2_1/2 3_1/4 add 5 3/4
c [2 1/2] [3 1/4] add 5 3/4
c 2-1/2 3-1/4 add 5 3/4

Str/Val

The type Str is a string of bytes is the native type of values stored on the stack. The parse function accepts any value and the formatting function uses the string as-is.

The type Val is used when an operation doesn't depend on the type of the value but is otherwise is the same as Str. It is used to notate operations such as swap where the types of the values being swapped is irrelevant.

Formatting Characters

Formatting characters are first removed when parsing numbers that are either an Integer, Decimal, or Float. Those characters are:

  • Thousand separators (',', '_', ' ')
  • Currency symbols ('$', '€', '¥')

The following strings all parse to the same number:

Input Stack
c 12,345.67 dec 12345.67
c 12_345.67 dec 12345.67
c '12_345.67' dec 12345.67
c $12,345.67 dec 12345.67
c 12,345.67$ dec 12345.67