Constant
A common mathematical constant value.
Math._constant(Math.PI)
There are several constant values that are important in calculations for science and engineering. The ||math.constant|| block provides several that you can use in your mathematical formulas and expressions.
π
The value of Pi (π) which is the ratio of a circle’s circumference to its diameter.
Math._constant(Math.PI)
Example
Get the area of a circle with a radius of 4.
let circle_area = Math.PI * 4**2
e
Euler’s number (e) which is the base of the natural logrithm and the exponential function.
Math._constant(Math.E)
Example
Find the half-life, in years, of radioactive decay for Carbon-14.
let time = 0
let decay = 0.000121
let carbon14 = 1
while (carbon14 > 0.5) {
carbon14 = Math.E ** (-1 * decay * time)
time += 1
}
ln(2)
Natural log of 2.
Math._constant(Math.LN2)
Example
Find out how many years will it take to double an investment using continuous compounding at 5% interest.
let years = Math.LN2 / 0.05
ln(10)
Natural log of 10.
Math._constant(Math.LN10)
Example
How many days will it take for bacteria in a culture to reach 10 times the start amount if they double in number each day.
let days = Math.LN10
log₂(e)
Convert from a natural logrithm to a base-2 logrithm.
Math._constant(Math.LOG2E)
The log₂(e) constant is equal to ln(e) / ln(2) which is also 1 / ln(2).
log₁₀(e)
Convert from a natural logrithm to a base-10 logrithm.
Math._constant(Math.LOG10E)
The log₁₀(e) constant is equal to 1 / ln(10) which is also 1 / ln(10).
√½
The square root of one half (1/2).
Math._constant(Math.SQRT1_2)
Example
Find the length of the sides of a square with a diagonal length of 9.
let side = 9 * Math.SQRT1_2
√2
The square root of 2.
Math._constant(Math.SQRT2)
Example
Find out how much shorter it is by walking across a square parking lot on a street corner than using the sidewalk on the sides. Each side of the parking lot is 50 meters.
let walk_diff = 2 * 50 - 50 * Math.SQRT2