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jax.numpy.expm1

jax.numpy.expm1(x)

Calculate exp(x) - 1 for all elements in the array.

LAX-backend implementation of expm1(). Original docstring below.

expm1(x, /, out=None, *, where=True, casting=’same_kind’, order=’K’, dtype=None, subok=True[, signature, extobj])

Parameters

x (array_like) – Input values.

Returns

out – Element-wise exponential minus one: out = exp(x) - 1. This is a scalar if x is a scalar.

Return type

ndarray or scalar

See also

log1p()

log(1 + x), the inverse of expm1.

Notes

This function provides greater precision than exp(x) - 1 for small values of x.

Examples

The true value of exp(1e-10) - 1 is 1.00000000005e-10 to about 32 significant digits. This example shows the superiority of expm1 in this case.

>>> np.expm1(1e-10)
1.00000000005e-10
>>> np.exp(1e-10) - 1
1.000000082740371e-10