Supported functions and constants
Everything the parser accepts is listed below; any other token is rejected for safety.
| Category | Available | Example |
|---|---|---|
| Trigonometry | sin, cos, tan, asin, acos, atan | sin(pi/2) = 1 (radians) |
| Roots and absolute value | sqrt, cbrt, abs | sqrt(16) = 4; cbrt(27) = 3 |
| Logs and exponential | ln, log (base 10), log2, exp | log(1000) = 3; ln(e) = 1 |
| Rounding | floor, ceil, round | floor(2.7) = 2; ceil(2.1) = 3 |
| Two-argument | min(a, b), max(a, b) | max(3, 7) = 7 |
| Constants | pi, e, tau | tau = 2 x pi = 6.283185... |
| Operators | + - * / % ^ and parentheses | 2^10 = 1024; 10 % 3 = 1 |
- The angle unit applies to trig functions only: degrees mode converts inputs of sin/cos/tan from degrees and returns asin/acos/atan results in degrees.
- log means base-10 logarithm here; use ln for the natural logarithm and log2 for base 2.
- The parser is a security whitelist: expressions are never passed to eval, and unrecognized identifiers make the whole expression invalid rather than guessing.
- Results are limited by double-precision floating-point arithmetic (about 15-16 significant digits); tiny rounding artifacts such as 0.30000000000000004 for 0.1 + 0.2 are inherent to floating point.
What is this scientific calculator?
A scientific calculator evaluates mathematical expressions that go beyond basic arithmetic: trigonometry, logarithms, exponentials, roots and constants. This one accepts a whole expression as text and applies the standard order of operations — parentheses first, then exponents, then multiplication, division and remainder, then addition and subtraction (PEMDAS/BODMAS).
Supported functions: sin, cos, tan and their inverses asin, acos, atan; sqrt (square root) and cbrt (cube root); abs (absolute value); ln (natural log), log (base-10 log), log2 (base-2 log) and exp (e raised to a power); floor, ceil and round; and two-argument min(a, b) and max(a, b). Supported constants: pi (3.14159...), e (2.71828...) and tau (2 x pi). Supported operators: + - * / % (remainder) and ^ (power), plus parentheses and unary minus.
The expression is evaluated by a safe whitelist parser: the input is tokenized against the fixed list of allowed functions, constants, numbers and operators, and anything outside that list is rejected. The calculator never passes your input to the JavaScript engine's eval, so arbitrary code can never run — unknown names simply produce no result.
The angle unit setting controls trigonometry: in degrees mode, arguments to sin, cos and tan are interpreted as degrees, and results of asin, acos and atan are returned in degrees. In radians mode (the mathematical default), all angles are in radians.
How to use this scientific calculator
- Type your expression, for example: sin(pi/6) + sqrt(16) * 2^3. Function arguments go in parentheses; multiplication must be written explicitly with * (write 2*pi, not 2pi).
- Choose the angle unit — radians or degrees — before evaluating trigonometric functions. sin(30) in degrees mode is 0.5; in radians mode it is about -0.988.
- Read the result. Very large or very small results are displayed in scientific e-notation.
- If no result appears, check for unbalanced parentheses, unknown function names, or implicit multiplication — the whitelist parser rejects anything it does not recognize.
Order of operations (PEMDAS)
Expressions are evaluated in this order: parentheses (innermost first), then function applications, then exponentiation ^ (right-associative), then unary minus, then * / and % left to right, then + and - left to right. This matches the standard PEMDAS/BODMAS convention taught in mathematics.
Worked example: sin(pi/6) + sqrt(16) * 2^3 in radians mode. Step 1 — parentheses and functions: pi/6 = 0.523599 and sin(0.523599) = 0.5; sqrt(16) = 4. Step 2 — exponent: 2^3 = 8. Step 3 — multiplication before addition: 4 * 8 = 32. Step 4 — addition: 0.5 + 32 = 32.5.
Two conventions worth noting: exponentiation is right-associative, so 2^3^2 = 2^(3^2) = 2^9 = 512, not (2^3)^2 = 64; and the % operator is the remainder (modulo) operation, so 10 % 3 = 1 — it does not mean percent.
Common mistakes
- Evaluating trig in the wrong angle unit: sin(30) is 0.5 only in degrees mode; in radians sin(30) is about -0.988.
- Writing implicit multiplication such as 2pi or 3(4+1) — the parser requires explicit *: 2*pi, 3*(4+1).
- Expecting % to mean percent: it is the remainder operator, so 50 % 8 = 2; to take 50 percent of 8, write 0.5*8.
- Misreading operator precedence: -3^2 evaluates the power first, giving -9; write (-3)^2 for 9.
- Assuming left associativity of powers: 2^3^2 is 2^(3^2) = 512, not 64.
Часто задаваемые вопросы
What functions does this scientific calculator support?
Trigonometric functions sin, cos, tan and inverses asin, acos, atan; roots sqrt and cbrt; abs; logarithms ln (natural), log (base 10) and log2; exp; rounding functions floor, ceil and round; two-argument min and max; the constants pi, e and tau; and the operators + - * / % ^ with parentheses. Anything outside this list is rejected by the whitelist parser.
How do I switch between degrees and radians?
Use the angle unit selector. In degrees mode, sin, cos and tan interpret their arguments as degrees and the inverse functions return degrees; in radians mode everything uses radians, the mathematical default. The same expression can give different results in the two modes: sin(30) is 0.5 in degrees but about -0.988 in radians.
What order of operations does the calculator use?
The standard PEMDAS convention: parentheses first, then functions, then exponentiation (right-associative), then unary minus, then multiplication, division and remainder left to right, then addition and subtraction left to right. So 1 + 2 * 3^2 = 1 + 2 * 9 = 19, and 2^3^2 = 2^9 = 512.
Why does my expression return no result?
The parser accepts only whitelisted tokens. Common causes: implicit multiplication (write 2*pi, not 2pi), unbalanced parentheses, unknown function names (the supported list is fixed), invalid math such as sqrt of a negative number or division producing infinity, or expressions longer than 300 characters. Rejection is deliberate — the calculator never guesses and never executes arbitrary code.
What does the % operator do?
It computes the remainder of a division (the modulo operation): 10 % 3 = 1 because 10 = 3 x 3 + 1. It does not compute percentages. To calculate a percentage, use multiplication: 15% of 80 is 0.15*80 = 12.
Is it safe to type anything into the expression box?
Yes. The input is processed by a hand-written whitelist tokenizer and a shunting-yard evaluator; it is never passed to JavaScript's eval or any code-execution mechanism. Tokens outside the fixed whitelist of numbers, listed functions, constants and operators cause the expression to be rejected outright.
Источники
- ISO 80000-2:2019. Quantities and units — Part 2: Mathematics (standard notation for functions, logarithms and angular measure).
- Abramowitz M, Stegun IA (eds). Handbook of Mathematical Functions. National Bureau of Standards, 1964 (definitions of elementary transcendental functions).
- Weisstein, Eric W. "Precedence." MathWorld — A Wolfram Web Resource. mathworld.wolfram.com.