Function expm1 #
Calculate the value of subtracting 1 from the exponential value.
This function is more accurate than math.exp(x)-1 when x is near 0
To avoid ambiguity with the matrix exponential expm, this function
does not operate on matrices; if you wish to apply it elementwise, see
the examples.
Syntax #
Parameters #
| Parameter |
Type |
Description |
x |
number | BigNumber | Complex |
The number to exponentiate |
Returns #
| Type |
Description |
| number | BigNumber | Complex |
Exponential of x, minus one |
Throws #
Type | Description
—- | ———–
Examples #
math.expm1(2) // returns number 6.38905609893065
math.pow(math.e, 2) - 1 // returns number 6.3890560989306495
math.expm1(1e-8) // returns number 1.0000000050000001e-8
math.exp(1e-8) - 1 // returns number 9.9999999392253e-9
math.log(math.expm1(2) + 1) // returns number 2
math.map([1, 2, 3], math.expm1)
// returns [1.718281828459045, 6.3890560989306495, 19.085536923187668]
See also #
exp,
expm,
log,
pow
History #
| Version |
Comment |
| v11 |
Don’t apply elementwise, avoids confusion with matrix exponential |
| v4.2 |
Created |
