Four scientific calculators (using binary numbers internally):
- pycalc_light (light theme)
- pycalc_dark (dark theme)
- pycalc_lcars (LCARS theme)
- pycalc_units (converts from US units to metric units, e.g. to l, m, m², and kg)
There is also pycalc_desk, a four-function calculator using decimal internally, based on Python's decimal module.
The decimal calculator is useful to avoid the rounding errors of the binary calculators due to their decimal➜binary➜decimal conversions, which is better for e.g. financial calculations. It also has memory (M+ to add, MR to recall value, AC to clear) and the comma is used as a decimal separator in results.
For the unit converter, just attach the unit to the numerical value. E.g. to convert 1.5 quarts to liters, use "1.5_qt". If you would like to divide by a value, put the number and unit in parentheses, e.g. "(1.5_qt)", otherwise the result will be wrong!
The scientific calculators work the same as the Python math module in interactive mode:
- They use binary numbers internally, not decimal, so it has the usual rounding errors when comparing its results to a decimal calculator, e.g. "0.1 + 0.2" does not evaluate to exactly 0.3.
- The green buttons are for base conversion (hex/oct/bin) and entering numbers in other bases (0x, 0o, 0b).
- The trigonometric functions all input or output angles in rad of course, so use "rad" and "deg" to convert accordingly.
- "fah" and "cel" are Fahrenheit/Celsius conversion. E.g. "cel(100)" converts 100°F to Celsius. They also demonstrate how to add custom functions to the calculator.
- The imaginary unit j has a button. Note that not all Python math functions work with imaginary numbers, e.g. "exp" does not but "**2" does. Also "abs" is useful for imaginary numbers, e.g. "abs(3+4j)" = 5.
- SCI displays the result in scientific notation, pressing "=" switches back to normal display.
- The "e" button has multiple functions: As a variable, it is 2.718… (see table below); it is also used for entering numbers in scientific notation, e.g. 2e18; and it is the hex digit that equals 14.
- You can get asin, acos, and atan by first typing "a" from the hex block and then sin/cos/tan.
The hex buttons (a to f) and "j" can also be used as these predefined variables (a, b) or constants:
| Button | Equals |
|---|---|
| a | last computed answer |
| b | next-to-last answer |
| c | speed of light in m/s |
| d | Avogadro constant, molecules per mole |
| e | Euler's number 2.718… |
| f | gravitational constant in m³/(kg s) |
| j | astronomical unit (AU) in m |
Public Domain / CC0
- Digital-7 Mono by Sizenko Alexander
- Antonio by Vernon Adams
- Fixedsys Excelsior 2.00 by Darien Valentine
- OCRA by Matthew Skala