time-to-botec/squiggle/node_modules/@stdlib/stats/base/snanvariancech/docs/repl.txt

122 lines
4.2 KiB
Plaintext
Raw Normal View History

{{alias}}( N, correction, x, stride )
Computes the variance of a single-precision floating-point strided array
ignoring `NaN` values and using a one-pass trial mean algorithm.
The `N` and `stride` parameters determine which elements in `x` are accessed
at runtime.
Indexing is relative to the first index. To introduce an offset, use a typed
array view.
If `N <= 0`, the function returns `NaN`.
If every indexed element is `NaN`, the function returns `NaN`.
Parameters
----------
N: integer
Number of indexed elements.
correction: number
Degrees of freedom adjustment. Setting this parameter to a value other
than `0` has the effect of adjusting the divisor during the calculation
of the variance according to `n - c` where `c` corresponds to the
provided degrees of freedom adjustment and `n` corresponds to the number
of non-`NaN` indexed elements. When computing the variance of a
population, setting this parameter to `0` is the standard choice (i.e.,
the provided array contains data constituting an entire population).
When computing the unbiased sample variance, setting this parameter to
`1` is the standard choice (i.e., the provided array contains data
sampled from a larger population; this is commonly referred to as
Bessel's correction).
x: Float32Array
Input array.
stride: integer
Index increment.
Returns
-------
out: number
The variance.
Examples
--------
// Standard Usage:
> var x = new {{alias:@stdlib/array/float32}}( [ 1.0, -2.0, NaN, 2.0 ] );
> {{alias}}( x.length, 1, x, 1 )
~4.3333
// Using `N` and `stride` parameters:
> x = new {{alias:@stdlib/array/float32}}( [ -2.0, 1.0, 1.0, -5.0, 2.0, -1.0 ] );
> var N = {{alias:@stdlib/math/base/special/floor}}( x.length / 2 );
> {{alias}}( N, 1, x, 2 )
~4.3333
// Using view offsets:
> var x0 = new {{alias:@stdlib/array/float32}}( [ 1.0, -2.0, 3.0, 2.0, 5.0, -1.0 ] );
> var x1 = new {{alias:@stdlib/array/float32}}( x0.buffer, x0.BYTES_PER_ELEMENT*1 );
> N = {{alias:@stdlib/math/base/special/floor}}( x0.length / 2 );
> {{alias}}( N, 1, x1, 2 )
~4.3333
{{alias}}.ndarray( N, correction, x, stride, offset )
Computes the variance of a single-precision floating-point strided array
ignoring `NaN` values and using a one-pass trial mean algorithm and
alternative indexing semantics.
While typed array views mandate a view offset based on the underlying
buffer, the `offset` parameter supports indexing semantics based on a
starting index.
Parameters
----------
N: integer
Number of indexed elements.
correction: number
Degrees of freedom adjustment. Setting this parameter to a value other
than `0` has the effect of adjusting the divisor during the calculation
of the variance according to `n - c` where `c` corresponds to the
provided degrees of freedom adjustment and `n` corresponds to the number
of non-`NaN` indexed elements. When computing the variance of a
population, setting this parameter to `0` is the standard choice (i.e.,
the provided array contains data constituting an entire population).
When computing the unbiased sample variance, setting this parameter to
`1` is the standard choice (i.e., the provided array contains data
sampled from a larger population; this is commonly referred to as
Bessel's correction).
x: Float32Array
Input array.
stride: integer
Index increment.
offset: integer
Starting index.
Returns
-------
out: number
The variance.
Examples
--------
// Standard Usage:
> var x = new {{alias:@stdlib/array/float32}}( [ 1.0, -2.0, NaN, 2.0 ] );
> {{alias}}.ndarray( x.length, 1, x, 1, 0 )
~4.3333
// Using offset parameter:
> var x = new {{alias:@stdlib/array/float32}}( [ 1.0, -2.0, 3.0, 2.0, 5.0, -1.0 ] );
> var N = {{alias:@stdlib/math/base/special/floor}}( x.length / 2 );
> {{alias}}.ndarray( N, 1, x, 2, 1 )
~4.3333
See Also
--------