10 unstable releases (3 breaking)
0.4.0 | Jul 22, 2024 |
---|---|
0.3.3 | Jul 3, 2024 |
0.2.2 | Jun 30, 2024 |
0.1.1 | Jun 30, 2024 |
#163 in Math
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345KB
9K
SLoC
String Calculator
A small package containing eval methods to compute formulas inside strings.
How to use
Simply import the eval you need and use it.
use string_calculator::eval_f64;
fn main() {
println!("{}", eval_f64("(2+3) / 2".to_string(), 0.0)); // 2.5
}
Features
By default, all features are enabled. If you only want a specific eval method, use the feature associated with it's name in the list:
eval_complex
eval_decimal
eval_f64
eval_i64
eval_number
Example:
[dependencies]
string_calculator = { version = "0.4", default-features = false, features = ["eval_decimal"] }
Operators
Since there's a lot of things that could be simplified visually, here's the full list of operators implemented.
- Add (x+y)
This operator handle the addition between two number.
Example:
1 + 2
= 3
- Subtract (x-y)
This operator handle the subtraction between two number.
Example:
2 - 1
= 1
- Multiply (x*y)
This operator handle the multiplication between two number.
Example:
3 * 2
= 6
- Divide (x/y)
This operator handle the division between two number.
Example:
4 / 2
= 2
- Modulo (x%y) (only in
eval_decimal
,eval_number
,eval_f64
andeval_i64
) This operator handle the rest of the euclidian division between two number. Example:4 % 2
= 0
- Left Shift (x<<y) (only in
eval_i64
) This operator shift the bits ofx
toy
positions to the left (it's the same as multiplying by2^y
). Example:1 << 2
= 4
- Right Shift (x>>y) (only in
eval_i64
) This operator shift the bits ofx
toy
positions to the right (it's the same as dividing by2^y
). Example:4 >> 2
= 1
- PowerOf (x^y)
This operator handle the power of
x
byy
,x
andy
being both numbers. Example:3^3
= 27
- Subscript support (x²)
This operator handle the power of
x
by using the superscript notation (such as²
) for integers,x
being a number. Example:5²
= 25
- Factorial (x!) (only in
eval_decimal
,eval_number
,eval_f64
andeval_i64
) This operator handle the factorial of a realx
. Example:5!
= 120
- DegToRad (x°) (only in
eval_complex
,eval_number
andeval_f64
) This operator handle the conversion from degree to radian. You should note that it's priority is the same as multiplication. Example:3°
= 0.05235987755982989
- RadToDeg (x rad) (only in
eval_complex
,eval_number
andeval_f64
) This operator handle the conversion from radian to degree. You should note that it's priority is the same as multiplication. Example:3 rad
= 171.8873385393
Constants
- Pi (π) (only in
eval_complex
,eval_number
,eval_decimal
andeval_f64
) Pi is available aspi
orπ
. - E (e) (only in
eval_complex
,eval_number
,eval_decimal
andeval_f64
) E is available ase
.
Function notation
Some function can be written purely using their original mathematical notation if wanted.
- Floor (⌊x⌋) (only in
eval_f64
,eval_number
andeval_decimal
) This function gives the greatest integer less than or equal tox
. Example:⌊2.4⌋
= 2
- Ceiling (⌈x⌉) (only in
eval_f64
,eval_number
andeval_decimal
) This function gives the smallest integer greater or equal tox
. Example:⌈2.4⌉
= 3
Functions
- Absolute value (abs(x))
- Signum (sgn(x), sign(x), signum(x)) (only in
eval_decimal
,eval_f64
,eval_number
andeval_i64
) - Power (pow(x,y))
- Square root (sqrt(x))
- Root (root(x, n))
- Modulo (mod(x,y)) (only in
eval_decimal
,eval_number
,eval_f64
andeval_i64
) - Exponential (exp(x), exp2(x))
- Logarithm (ln(x), lb(x), log(x, b))
- Extremum (min(...X), max(...X)) (only in
eval_decimal
,eval_number
,eval_f64
andeval_i64
) - Avg (avg(...X)) (only in
eval_decimal
,eval_number
,eval_f64
andeval_i64
) - Median (median(...X), med(...X)) (only in
eval_decimal
,eval_number
,eval_f64
andeval_i64
) - Truncate (trunc(x), truncate(x)) (only in
eval_f64
,eval_number
andeval_decimal
) - Floor (floor(x)) (only in
eval_f64
,eval_number
andeval_decimal
) - Ceil (ceil(x)) (only in
eval_f64
,eval_number
andeval_decimal
) - Round (round(x)) (only in
eval_f64
,eval_number
andeval_decimal
) - Lambert W (lambert_w(x), w(x)) (only in
eval_f64
,eval_number
andeval_decimal
) - Iterated Logarithm (ilog(x, b)) (only in
eval_f64
,eval_number
andeval_decimal
) - Sin (sin(θ)) (only in
eval_complex
,eval_number
andeval_f64
) - Asin (asin(x)) (only in
eval_complex
,eval_number
andeval_f64
) - cos (cos(θ)) (only in
eval_complex
,eval_number
andeval_f64
) - Acos (acos(x)) (only in
eval_complex
,eval_number
andeval_f64
) - Tan (tan(θ)) (only in
eval_complex
,eval_number
andeval_f64
) - Atan (atan(x)) (only in
eval_complex
,eval_number
andeval_f64
) - Sinh (sinh(θ)) (only in
eval_complex
,eval_number
andeval_f64
) - Asinh (asinh(x), arsinh(x)) (only in
eval_complex
,eval_number
andeval_f64
) - Cosh (cosh(θ)) (only in
eval_complex
,eval_number
andeval_f64
) - Acosh (acosh(x), arcosh(x)) (only in
eval_complex
,eval_number
andeval_f64
) - Tanh (tanh(θ)) (only in
eval_complex
,eval_number
andeval_f64
) - Atanh (atanh(x), artanh(x)) (only in
eval_complex
,eval_number
andeval_f64
) - Atan 2 (atan2(y, x)) (only in
eval_f64
andeval_number
) - GCD (gcd(...X)) (only in
eval_i64
) - LCM (lcm(...X)) (only in
eval_i64
)
Placeholder Getter
The @
symbol is used here as a placeholder for the value you want to put into the eval_XXXXX
.
In the case you're writting a calculator, it might be useful to use your previous answer for example.
Dependencies
~160KB