numpy.seterr#
- numpy.seterr(all=None, divide=None, over=None, under=None, invalid=None)[source]#
Set how floating-point errors are handled.
Note that operations on integer scalar types (such as
int16
) are handled like floating point, and are affected by these settings.- Parameters:
- all{‘ignore’, ‘warn’, ‘raise’, ‘call’, ‘print’, ‘log’}, optional
Set treatment for all types of floating-point errors at once:
ignore: Take no action when the exception occurs.
warn: Print a
RuntimeWarning
(via the Pythonwarnings
module).raise: Raise a
FloatingPointError
.call: Call a function specified using the
seterrcall
function.print: Print a warning directly to
stdout
.log: Record error in a Log object specified by
seterrcall
.
The default is not to change the current behavior.
- divide{‘ignore’, ‘warn’, ‘raise’, ‘call’, ‘print’, ‘log’}, optional
Treatment for division by zero.
- over{‘ignore’, ‘warn’, ‘raise’, ‘call’, ‘print’, ‘log’}, optional
Treatment for floating-point overflow.
- under{‘ignore’, ‘warn’, ‘raise’, ‘call’, ‘print’, ‘log’}, optional
Treatment for floating-point underflow.
- invalid{‘ignore’, ‘warn’, ‘raise’, ‘call’, ‘print’, ‘log’}, optional
Treatment for invalid floating-point operation.
- Returns:
- old_settingsdict
Dictionary containing the old settings.
See also
seterrcall
Set a callback function for the ‘call’ mode.
geterr
,geterrcall
,errstate
Notes
The floating-point exceptions are defined in the IEEE 754 standard [1]:
Division by zero: infinite result obtained from finite numbers.
Overflow: result too large to be expressed.
Underflow: result so close to zero that some precision was lost.
Invalid operation: result is not an expressible number, typically indicates that a NaN was produced.
Examples
>>> orig_settings = np.seterr(all='ignore') # seterr to known value >>> np.int16(32000) * np.int16(3) 30464 >>> np.seterr(over='raise') {'divide': 'ignore', 'over': 'ignore', 'under': 'ignore', 'invalid': 'ignore'} >>> old_settings = np.seterr(all='warn', over='raise') >>> np.int16(32000) * np.int16(3) Traceback (most recent call last): File "<stdin>", line 1, in <module> FloatingPointError: overflow encountered in scalar multiply
>>> old_settings = np.seterr(all='print') >>> np.geterr() {'divide': 'print', 'over': 'print', 'under': 'print', 'invalid': 'print'} >>> np.int16(32000) * np.int16(3) 30464 >>> np.seterr(**orig_settings) # restore original {'divide': 'print', 'over': 'print', 'under': 'print', 'invalid': 'print'}