# numpy.lib.scimath.log10¶

lib.scimath.log10(x)[source]

Compute the logarithm base 10 of x.

Return the “principal value” (for a description of this, see numpy.log10) of $$log_{10}(x)$$. For real x > 0, this is a real number (log10(0) returns -inf and log10(np.inf) returns inf). Otherwise, the complex principle value is returned.

Parameters
xarray_like or scalar

The value(s) whose log base 10 is (are) required.

Returns
outndarray or scalar

The log base 10 of the x value(s). If x was a scalar, so is out, otherwise an array object is returned.

Notes

For a log10() that returns NAN when real x < 0, use numpy.log10 (note, however, that otherwise numpy.log10 and this log10 are identical, i.e., both return -inf for x = 0, inf for x = inf, and, notably, the complex principle value if x.imag != 0).

Examples

(We set the printing precision so the example can be auto-tested)

>>> np.set_printoptions(precision=4)

>>> np.emath.log10(10**1)
1.0

>>> np.emath.log10([-10**1, -10**2, 10**2])
array([1.+1.3644j, 2.+1.3644j, 2.+0.j    ])