qspec.analyze.straight_x_std  (  x ,  b ,  sigma_x ,  sigma_a ,  sigma_b ,  corr_ab  )[source]

The standard deviation of a straight $$\sigma_f(x) = \sqrt{\sigma_a^2 + (x\sigma_b)^2 + 2x\sigma_a\sigma_b\rho_{ab} + (b\sigma_x)^2 + (\sigma_b\sigma_x)^2}.$$

Parameters:

xarray_like

The $x$ values.

barray_like

The slope $b$.

sigma_xarray_like

The standard deviation $\sigma_x$ of the x values.

sigma_aarray_like

The standard deviation $\sigma_a$ of the y-intercept.

sigma_barray_like

The standard deviation $\sigma_b$ of the slope b.

corr_abarray_like

The correlation coefficient $\rho_{ab}$ between the slope b and the y-intercept.

Returns:

sigma_fndarray

The standard deviation $\sigma_f$ of a straight line.